/*
** Generate code to do an analysis of all indices associated with
** a single table.
*/
static void analyzeOneTable(
Parse *pParse, /* Parser context */
Table *pTab, /* Table whose indices are to be analyzed */
Index *pOnlyIdx, /* If not NULL, only analyze this one index */
int iStatCur, /* Index of VdbeCursor that writes the sqlite_stat1 table */
int iMem /* Available memory locations begin here */
){
sqlite3 *db = pParse->db; /* Database handle */
Index *pIdx; /* An index to being analyzed */
int iIdxCur; /* Cursor open on index being analyzed */
Vdbe *v; /* The virtual machine being built up */
int i; /* Loop counter */
int topOfLoop; /* The top of the loop */
int endOfLoop; /* The end of the loop */
int jZeroRows = -1; /* Jump from here if number of rows is zero */
int iDb; /* Index of database containing pTab */
int regTabname = iMem++; /* Register containing table name */
int regIdxname = iMem++; /* Register containing index name */
int regSampleno = iMem++; /* Register containing next sample number */
int regCol = iMem++; /* Content of a column analyzed table */
int regRec = iMem++; /* Register holding completed record */
int regTemp = iMem++; /* Temporary use register */
int regRowid = iMem++; /* Rowid for the inserted record */
#ifdef SQLITE_ENABLE_STAT2
int addr = 0; /* Instruction address */
int regTemp2 = iMem++; /* Temporary use register */
int regSamplerecno = iMem++; /* Index of next sample to record */
int regRecno = iMem++; /* Current sample index */
int regLast = iMem++; /* Index of last sample to record */
int regFirst = iMem++; /* Index of first sample to record */
#endif
v = sqlite3GetVdbe(pParse);
if( v==0 || NEVER(pTab==0) ){
return;
}
if( pTab->tnum==0 ){
/* Do not gather statistics on views or virtual tables */
return;
}
if( memcmp(pTab->zName, "sqlite_", 7)==0 ){
/* Do not gather statistics on system tables */
return;
}
assert( sqlite3BtreeHoldsAllMutexes(db) );
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb>=0 );
assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
#ifndef SQLITE_OMIT_AUTHORIZATION
if( sqlite3AuthCheck(pParse, SQLITE_ANALYZE, pTab->zName, 0,
db->aDb[iDb].zName ) ){
return;
}
#endif
/* Establish a read-lock on the table at the shared-cache level. */
sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
iIdxCur = pParse->nTab++;
sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
int nCol;
KeyInfo *pKey;
if( pOnlyIdx && pOnlyIdx!=pIdx ) continue;
nCol = pIdx->nColumn;
pKey = sqlite3IndexKeyinfo(pParse, pIdx);
if( iMem+1+(nCol*2)>pParse->nMem ){
pParse->nMem = iMem+1+(nCol*2);
}
/* Open a cursor to the index to be analyzed. */
assert( iDb==sqlite3SchemaToIndex(db, pIdx->pSchema) );
sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
(char *)pKey, P4_KEYINFO_HANDOFF);
VdbeComment((v, "%s", pIdx->zName));
/* Populate the register containing the index name. */
sqlite3VdbeAddOp4(v, OP_String8, 0, regIdxname, 0, pIdx->zName, 0);
#ifdef SQLITE_ENABLE_STAT2
/* If this iteration of the loop is generating code to analyze the
** first index in the pTab->pIndex list, then register regLast has
** not been populated. In this case populate it now. */
if( pTab->pIndex==pIdx ){
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regSamplerecno);
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2-1, regTemp);
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2, regTemp2);
sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regLast);
sqlite3VdbeAddOp2(v, OP_Null, 0, regFirst);
addr = sqlite3VdbeAddOp3(v, OP_Lt, regSamplerecno, 0, regLast);
sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regLast, regFirst);
sqlite3VdbeAddOp3(v, OP_Multiply, regLast, regTemp, regLast);
sqlite3VdbeAddOp2(v, OP_AddImm, regLast, SQLITE_INDEX_SAMPLES*2-2);
sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regLast, regLast);
sqlite3VdbeJumpHere(v, addr);
}
/* Zero the regSampleno and regRecno registers. */
sqlite3VdbeAddOp2(v, OP_Integer, 0, regSampleno);
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRecno);
sqlite3VdbeAddOp2(v, OP_Copy, regFirst, regSamplerecno);
#endif
/* The block of memory cells initialized here is used as follows.
**
** iMem:
** The total number of rows in the table.
**
** iMem+1 .. iMem+nCol:
** Number of distinct entries in index considering the
** left-most N columns only, where N is between 1 and nCol,
** inclusive.
**
** iMem+nCol+1 .. Mem+2*nCol:
** Previous value of indexed columns, from left to right.
**
** Cells iMem through iMem+nCol are initialized to 0. The others are
** initialized to contain an SQL NULL.
*/
for(i=0; i<=nCol; i++){
sqlite3VdbeAddOp2(v, OP_Integer, 0, iMem+i);
}
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp2(v, OP_Null, 0, iMem+nCol+i+1);
}
/* Start the analysis loop. This loop runs through all the entries in
** the index b-tree. */
endOfLoop = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
topOfLoop = sqlite3VdbeCurrentAddr(v);
sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);
for(i=0; i<nCol; i++){
CollSeq *pColl;
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
if( i==0 ){
#ifdef SQLITE_ENABLE_STAT2
/* Check if the record that cursor iIdxCur points to contains a
** value that should be stored in the sqlite_stat2 table. If so,
** store it. */
int ne = sqlite3VdbeAddOp3(v, OP_Ne, regRecno, 0, regSamplerecno);
assert( regTabname+1==regIdxname
&& regTabname+2==regSampleno
&& regTabname+3==regCol
);
sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 4, regRec, "aaab", 0);
sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur+1, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, iStatCur+1, regRec, regRowid);
/* Calculate new values for regSamplerecno and regSampleno.
**
** sampleno = sampleno + 1
** samplerecno = samplerecno+(remaining records)/(remaining samples)
*/
sqlite3VdbeAddOp2(v, OP_AddImm, regSampleno, 1);
sqlite3VdbeAddOp3(v, OP_Subtract, regRecno, regLast, regTemp);
sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regTemp2);
sqlite3VdbeAddOp3(v, OP_Subtract, regSampleno, regTemp2, regTemp2);
sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regTemp, regTemp);
sqlite3VdbeAddOp3(v, OP_Add, regSamplerecno, regTemp, regSamplerecno);
sqlite3VdbeJumpHere(v, ne);
sqlite3VdbeAddOp2(v, OP_AddImm, regRecno, 1);
#endif
/* Always record the very first row */
sqlite3VdbeAddOp1(v, OP_IfNot, iMem+1);
}
assert( pIdx->azColl!=0 );
assert( pIdx->azColl[i]!=0 );
pColl = sqlite3LocateCollSeq(pParse, pIdx->azColl[i]);
sqlite3VdbeAddOp4(v, OP_Ne, regCol, 0, iMem+nCol+i+1,
(char*)pColl, P4_COLLSEQ);
sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
}
if( db->mallocFailed ){
/* If a malloc failure has occurred, then the result of the expression
** passed as the second argument to the call to sqlite3VdbeJumpHere()
** below may be negative. Which causes an assert() to fail (or an
** out-of-bounds write if SQLITE_DEBUG is not defined). */
return;
}
sqlite3VdbeAddOp2(v, OP_Goto, 0, endOfLoop);
for(i=0; i<nCol; i++){
int addr2 = sqlite3VdbeCurrentAddr(v) - (nCol*2);
if( i==0 ){
sqlite3VdbeJumpHere(v, addr2-1); /* Set jump dest for the OP_IfNot */
}
sqlite3VdbeJumpHere(v, addr2); /* Set jump dest for the OP_Ne */
sqlite3VdbeAddOp2(v, OP_AddImm, iMem+i+1, 1);
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, iMem+nCol+i+1);
}
/* End of the analysis loop. */
sqlite3VdbeResolveLabel(v, endOfLoop);
sqlite3VdbeAddOp2(v, OP_Next, iIdxCur, topOfLoop);
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
/* Store the results in sqlite_stat1.
**
** The result is a single row of the sqlite_stat1 table. The first
** two columns are the names of the table and index. The third column
** is a string composed of a list of integer statistics about the
** index. The first integer in the list is the total number of entries
** in the index. There is one additional integer in the list for each
** column of the table. This additional integer is a guess of how many
** rows of the table the index will select. If D is the count of distinct
** values and K is the total number of rows, then the integer is computed
** as:
**
** I = (K+D-1)/D
**
** If K==0 then no entry is made into the sqlite_stat1 table.
** If K>0 then it is always the case the D>0 so division by zero
** is never possible.
*/
sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regSampleno);
if( jZeroRows<0 ){
jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
}
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
sqlite3VdbeAddOp3(v, OP_Add, iMem, iMem+i+1, regTemp);
sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
sqlite3VdbeAddOp3(v, OP_Divide, iMem+i+1, regTemp, regTemp);
sqlite3VdbeAddOp1(v, OP_ToInt, regTemp);
sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
}
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
}
/* If the table has no indices, create a single sqlite_stat1 entry
** containing NULL as the index name and the row count as the content.
*/
if( pTab->pIndex==0 ){
sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
VdbeComment((v, "%s", pTab->zName));
sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regSampleno);
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, regSampleno);
}else{
sqlite3VdbeJumpHere(v, jZeroRows);
jZeroRows = sqlite3VdbeAddOp0(v, OP_Goto);
}
sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
if( pParse->nMem<regRec ) pParse->nMem = regRec;
sqlite3VdbeJumpHere(v, jZeroRows);
}
/*
** This is called to code FOR EACH ROW triggers.
**
** When the code that this function generates is executed, the following
** must be true:
**
** 1. No cursors may be open in the main database. (But newIdx and oldIdx
** can be indices of cursors in temporary tables. See below.)
**
** 2. If the triggers being coded are ON INSERT or ON UPDATE triggers, then
** a temporary vdbe cursor (index newIdx) must be open and pointing at
** a row containing values to be substituted for new.* expressions in the
** trigger program(s).
**
** 3. If the triggers being coded are ON DELETE or ON UPDATE triggers, then
** a temporary vdbe cursor (index oldIdx) must be open and pointing at
** a row containing values to be substituted for old.* expressions in the
** trigger program(s).
**
** If they are not NULL, the piOldColMask and piNewColMask output variables
** are set to values that describe the columns used by the trigger program
** in the OLD.* and NEW.* tables respectively. If column N of the
** pseudo-table is read at least once, the corresponding bit of the output
** mask is set. If a column with an index greater than 32 is read, the
** output mask is set to the special value 0xffffffff.
**
*/
int sqlite3CodeRowTrigger(
Parse *pParse, /* Parse context */
Trigger *pTrigger, /* List of triggers on table pTab */
int op, /* One of TK_UPDATE, TK_INSERT, TK_DELETE */
ExprList *pChanges, /* Changes list for any UPDATE OF triggers */
int tr_tm, /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
Table *pTab, /* The table to code triggers from */
int newIdx, /* The indice of the "new" row to access */
int oldIdx, /* The indice of the "old" row to access */
int orconf, /* ON CONFLICT policy */
int ignoreJump, /* Instruction to jump to for RAISE(IGNORE) */
u32 *piOldColMask, /* OUT: Mask of columns used from the OLD.* table */
u32 *piNewColMask /* OUT: Mask of columns used from the NEW.* table */
){
Trigger *p;
sqlite3 *db = pParse->db;
TriggerStack trigStackEntry;
trigStackEntry.oldColMask = 0;
trigStackEntry.newColMask = 0;
assert(op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE);
assert(tr_tm == TRIGGER_BEFORE || tr_tm == TRIGGER_AFTER );
assert(newIdx != -1 || oldIdx != -1);
for(p=pTrigger; p; p=p->pNext){
int fire_this = 0;
/* Sanity checking: The schema for the trigger and for the table are
** always defined. The trigger must be in the same schema as the table
** or else it must be a TEMP trigger. */
assert( p->pSchema!=0 );
assert( p->pTabSchema!=0 );
assert( p->pSchema==p->pTabSchema || p->pSchema==db->aDb[1].pSchema );
/* Determine whether we should code this trigger */
if(
p->op==op &&
p->tr_tm==tr_tm &&
checkColumnOverlap(p->pColumns,pChanges)
){
TriggerStack *pS; /* Pointer to trigger-stack entry */
for(pS=pParse->trigStack; pS && p!=pS->pTrigger; pS=pS->pNext){}
if( !pS ){
fire_this = 1;
}
#if 0 /* Give no warning for recursive triggers. Just do not do them */
else{
sqlite3ErrorMsg(pParse, "recursive triggers not supported (%s)",
p->name);
return SQLITE_ERROR;
}
#endif
}
if( fire_this ){
int endTrigger;
Expr * whenExpr;
AuthContext sContext;
NameContext sNC;
#ifndef SQLITE_OMIT_TRACE
sqlite3VdbeAddOp4(pParse->pVdbe, OP_Trace, 0, 0, 0,
sqlite3MPrintf(db, "-- TRIGGER %s", p->name),
P4_DYNAMIC);
#endif
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
/* Push an entry on to the trigger stack */
trigStackEntry.pTrigger = p;
trigStackEntry.newIdx = newIdx;
trigStackEntry.oldIdx = oldIdx;
trigStackEntry.pTab = pTab;
trigStackEntry.pNext = pParse->trigStack;
trigStackEntry.ignoreJump = ignoreJump;
pParse->trigStack = &trigStackEntry;
sqlite3AuthContextPush(pParse, &sContext, p->name);
/* code the WHEN clause */
endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
whenExpr = sqlite3ExprDup(db, p->pWhen, 0);
if( db->mallocFailed || sqlite3ResolveExprNames(&sNC, whenExpr) ){
pParse->trigStack = trigStackEntry.pNext;
sqlite3ExprDelete(db, whenExpr);
return 1;
}
sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, SQLITE_JUMPIFNULL);
sqlite3ExprDelete(db, whenExpr);
codeTriggerProgram(pParse, p->step_list, orconf);
/* Pop the entry off the trigger stack */
pParse->trigStack = trigStackEntry.pNext;
sqlite3AuthContextPop(&sContext);
sqlite3VdbeResolveLabel(pParse->pVdbe, endTrigger);
}
}
if( piOldColMask ) *piOldColMask |= trigStackEntry.oldColMask;
if( piNewColMask ) *piNewColMask |= trigStackEntry.newColMask;
return 0;
}
/*
** Generate code for a DELETE FROM statement.
**
** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
** \________/ \________________/
** pTabList pWhere
*/
void sqlite3DeleteFrom(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table from which we should delete things */
Expr *pWhere /* The WHERE clause. May be null */
){
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
const char *zDb; /* Name of database holding pTab */
int end, addr = 0; /* A couple addresses of generated code */
int i; /* Loop counter */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Index *pIdx; /* For looping over indices of the table */
int iCur; /* VDBE Cursor number for pTab */
sqlite3 *db; /* Main database structure */
AuthContext sContext; /* Authorization context */
NameContext sNC; /* Name context to resolve expressions in */
int iDb; /* Database number */
int memCnt = -1; /* Memory cell used for change counting */
int rcauth; /* Value returned by authorization callback */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to delete from a view */
Trigger *pTrigger; /* List of table triggers, if required */
#endif
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto delete_from_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to delete. This table has to be
** put in an SrcList structure because some of the subroutines we
** will be calling are designed to work with multiple tables and expect
** an SrcList* parameter instead of just a Table* parameter.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto delete_from_cleanup;
/* Figure out if we have any triggers and if the table being
** deleted from is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
isView = pTab->pSelect!=0;
#else
# define pTrigger 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
/* If pTab is really a view, make sure it has been initialized.
*/
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto delete_from_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
goto delete_from_cleanup;
}
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
zDb = db->aDb[iDb].zName;
rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
if( rcauth==SQLITE_DENY ){
goto delete_from_cleanup;
}
assert(!isView || pTrigger);
/* Assign cursor number to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
iCur = pTabList->a[0].iCursor = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto delete_from_cleanup;
}
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, (pTrigger?1:0), iDb);
/* If we are trying to delete from a view, realize that view into
** a ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
}
#endif
/* Resolve the column names in the WHERE clause.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto delete_from_cleanup;
}
/* Initialize the counter of the number of rows deleted, if
** we are counting rows.
*/
if( db->flags & SQLITE_CountRows ){
memCnt = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
}
#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
/* Special case: A DELETE without a WHERE clause deletes everything.
** It is easier just to erase the whole table. Prior to version 3.6.5,
** this optimization caused the row change count (the value returned by
** API function sqlite3_count_changes) to be set incorrectly. */
if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab) ){
assert( !isView );
sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
pTab->zName, P4_STATIC);
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
}
}else
#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
/* The usual case: There is a WHERE clause so we have to scan through
** the table and pick which records to delete.
*/
{
int iRowSet = ++pParse->nMem; /* Register for rowset of rows to delete */
int iRowid = ++pParse->nMem; /* Used for storing rowid values. */
int regRowid; /* Actual register containing rowids */
/* Collect rowids of every row to be deleted.
*/
sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,0,WHERE_DUPLICATES_OK);
if( pWInfo==0 ) goto delete_from_cleanup;
regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid, 0);
sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);
if( db->flags & SQLITE_CountRows ){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
}
sqlite3WhereEnd(pWInfo);
/* Delete every item whose key was written to the list during the
** database scan. We have to delete items after the scan is complete
** because deleting an item can change the scan order. */
end = sqlite3VdbeMakeLabel(v);
/* Unless this is a view, open cursors for the table we are
** deleting from and all its indices. If this is a view, then the
** only effect this statement has is to fire the INSTEAD OF
** triggers. */
if( !isView ){
sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
}
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);
/* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVTab, P4_VTAB);
sqlite3MayAbort(pParse);
}else
#endif
{
int count = (pParse->nested==0); /* True to count changes */
sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, count, pTrigger, OE_Default);
}
/* End of the delete loop */
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeResolveLabel(v, end);
/* Close the cursors open on the table and its indexes. */
if( !isView && !IsVirtual(pTab) ){
for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
}
sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
}
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
/* Return the number of rows that were deleted. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){
sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC);
}
delete_from_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprDelete(db, pWhere);
return;
}
/*
** Process an UPDATE statement.
**
** UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
** \_______/ \________/ \______/ \________________/
* onError pTabList pChanges pWhere
*/
void sqlite3Update(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table in which we should change things */
ExprList *pChanges, /* Things to be changed */
Expr *pWhere, /* The WHERE clause. May be null */
int onError /* How to handle constraint errors */
){
int i, j; /* Loop counters */
Table *pTab; /* The table to be updated */
int addrTop = 0; /* VDBE instruction address of the start of the loop */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Vdbe *v; /* The virtual database engine */
Index *pIdx; /* For looping over indices */
Index *pPk; /* The PRIMARY KEY index for WITHOUT ROWID tables */
int nIdx; /* Number of indices that need updating */
int iBaseCur; /* Base cursor number */
int iDataCur; /* Cursor for the canonical data btree */
int iIdxCur; /* Cursor for the first index */
sqlite3 *db; /* The database structure */
int *aRegIdx = 0; /* One register assigned to each index to be updated */
int *aXRef = 0; /* aXRef[i] is the index in pChanges->a[] of the
** an expression for the i-th column of the table.
** aXRef[i]==-1 if the i-th column is not changed. */
u8 *aToOpen; /* 1 for tables and indices to be opened */
u8 chngPk; /* PRIMARY KEY changed in a WITHOUT ROWID table */
u8 chngRowid; /* Rowid changed in a normal table */
u8 chngKey; /* Either chngPk or chngRowid */
Expr *pRowidExpr = 0; /* Expression defining the new record number */
AuthContext sContext; /* The authorization context */
NameContext sNC; /* The name-context to resolve expressions in */
int iDb; /* Database containing the table being updated */
int okOnePass; /* True for one-pass algorithm without the FIFO */
int hasFK; /* True if foreign key processing is required */
int labelBreak; /* Jump here to break out of UPDATE loop */
int labelContinue; /* Jump here to continue next step of UPDATE loop */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True when updating a view (INSTEAD OF trigger) */
Trigger *pTrigger; /* List of triggers on pTab, if required */
int tmask; /* Mask of TRIGGER_BEFORE|TRIGGER_AFTER */
#endif
int newmask; /* Mask of NEW.* columns accessed by BEFORE triggers */
int iEph = 0; /* Ephemeral table holding all primary key values */
int nKey = 0; /* Number of elements in regKey for WITHOUT ROWID */
int aiCurOnePass[2]; /* The write cursors opened by WHERE_ONEPASS */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid; /* The old rowid */
int regNewRowid; /* The new rowid */
int regNew; /* Content of the NEW.* table in triggers */
int regOld = 0; /* Content of OLD.* table in triggers */
int regRowSet = 0; /* Rowset of rows to be updated */
int regKey = 0; /* composite PRIMARY KEY value */
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto update_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to update.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
#if defined(SQLITE_ENABLE_SELINUX)
if(0!=sqlite3StrNICmp(pTab->zName, "sqlite_", 7) && 0!=sqlite3StrNICmp(pTab->zName, "selinux_", 8)) {
/* MODIFIED */
Expr *pNewWhere = NULL;
char *f_name = sqlite3MPrintf(db, "%s", "selinux_check_access");
char *f_column = sqlite3MPrintf(db, "%s", "security_context");
char *f_class = sqlite3MPrintf(db, "%s", "db_tuple");
char *f_action = sqlite3MPrintf(db, "%s", "update");
for(i = 0; i < pTabList->nAlloc; i++){
Expr *pFName = sqlite3DbMallocZero(db, sizeof(Expr) + strlen(f_name) + 1);
Expr *pFTable = sqlite3DbMallocZero(db, sizeof(Expr) + strlen(pTabList->a[i].zName) + 1);
Expr *pFColumn = sqlite3DbMallocZero(db, sizeof(Expr) + strlen(f_column) + 1);
Expr *pFClass = sqlite3DbMallocZero(db, sizeof(Expr) + strlen(f_class) + 1);
Expr *pFAction = sqlite3DbMallocZero(db, sizeof(Expr) + strlen(f_action) + 1);
Expr *pFDebug = sqlite3DbMallocZero(db, sizeof(Expr) + strlen(pTabList->a[i].zName) + 1);
Expr *pFunction = sqlite3DbMallocZero(db, sizeof(Expr));
pFName->op = (u8)153;
pFName->iAgg = -1;
pFTable->op = (u8)27;
pFTable->iAgg = -1;
pFColumn->op = (u8)27;
pFColumn->iAgg = -1;
pFClass->op = (u8)97;
pFClass->iAgg = -1;
pFAction->op = (u8)97;
pFAction->iAgg = -1;
pFDebug->op = (u8)97;
pFDebug->iAgg = -1;
pFunction->op = (u8)122;
pFunction->iAgg = -1;
pFName->u.zToken = (char*)&pFName[1];
pFTable->u.zToken = (char*)&pFTable[1];
pFColumn->u.zToken = (char*)&pFColumn[1];
pFClass->u.zToken = (char*)&pFClass[1];
pFAction->u.zToken = (char*)&pFAction[1];
pFDebug->u.zToken = (char*)&pFDebug[1];
memcpy(pFName->u.zToken, f_name, strlen(f_name));
memcpy(pFTable->u.zToken, pTabList->a[i].zName, strlen(pTabList->a[i].zName));
memcpy(pFColumn->u.zToken, f_column, strlen(f_column));
memcpy(pFClass->u.zToken, f_class, strlen(f_class));
memcpy(pFAction->u.zToken, f_action, strlen(f_action));
memcpy(pFDebug->u.zToken, pTabList->a[i].zName, strlen(pTabList->a[i].zName));
pFName->u.zToken[strlen(f_name)] = 0;
pFTable->u.zToken[strlen(pTabList->a[i].zName)] = 0;
pFColumn->u.zToken[strlen(f_column)] = 0;
pFClass->u.zToken[strlen(f_class)] = 0;
pFAction->u.zToken[strlen(f_action)] = 0;
pFDebug->u.zToken[strlen(pTabList->a[i].zName)] = 0;
pFName->nHeight = 1;
pFTable->nHeight = 1;
pFColumn->nHeight = 1;
pFClass->nHeight = 1;
pFAction->nHeight = 1;
pFDebug->nHeight = 1;
sqlite3ExprAttachSubtrees(db, pFunction, pFTable, pFColumn);
ExprList *pExprFunction;
pExprFunction = sqlite3ExprListAppend(pParse, 0, pFunction);
pExprFunction = sqlite3ExprListAppend(pParse, pExprFunction, pFClass);
pExprFunction = sqlite3ExprListAppend(pParse, pExprFunction, pFAction);
pExprFunction = sqlite3ExprListAppend(pParse, pExprFunction, pFDebug);
pFName->x.pList = pExprFunction;
sqlite3ExprSetHeight(pParse, pFName);
if(pNewWhere)
pNewWhere = sqlite3ExprAnd(db, pFName, pNewWhere);
else
pNewWhere = pFName;
}
if(pWhere)
pWhere = sqlite3ExprAnd(db, pNewWhere, pWhere);
else
pWhere = pNewWhere;
}
/* ------------------------------------------------------------ */
#endif /* defined(SQLITE_ENABLE_SELINUX) */
/* Figure out if we have any triggers and if the table being
** updated is a view.
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges, &tmask);
isView = pTab->pSelect!=0;
assert( pTrigger || tmask==0 );
#else
# define pTrigger 0
# define isView 0
# define tmask 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, tmask) ){
goto update_cleanup;
}
/* Allocate a cursors for the main database table and for all indices.
** The index cursors might not be used, but if they are used they
** need to occur right after the database cursor. So go ahead and
** allocate enough space, just in case.
*/
pTabList->a[0].iCursor = iBaseCur = iDataCur = pParse->nTab++;
iIdxCur = iDataCur+1;
pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
if( pIdx->autoIndex==2 && pPk!=0 ){
iDataCur = pParse->nTab;
pTabList->a[0].iCursor = iDataCur;
}
pParse->nTab++;
}
/* Allocate space for aXRef[], aRegIdx[], and aToOpen[].
** Initialize aXRef[] and aToOpen[] to their default values.
*/
aXRef = sqlite3DbMallocRaw(db, sizeof(int) * (pTab->nCol+nIdx) + nIdx+2 );
if( aXRef==0 ) goto update_cleanup;
aRegIdx = aXRef+pTab->nCol;
aToOpen = (u8*)(aRegIdx+nIdx);
memset(aToOpen, 1, nIdx+1);
aToOpen[nIdx+1] = 0;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* Initialize the name-context */
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
/* Resolve the column names in all the expressions of the
** of the UPDATE statement. Also find the column index
** for each column to be updated in the pChanges array. For each
** column to be updated, make sure we have authorization to change
** that column.
*/
chngRowid = chngPk = 0;
for(i=0; i<pChanges->nExpr; i++){
if( sqlite3ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
goto update_cleanup;
}
for(j=0; j<pTab->nCol; j++){
if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
if( j==pTab->iPKey ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else if( pPk && (pTab->aCol[j].colFlags & COLFLAG_PRIMKEY)!=0 ){
chngPk = 1;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( pPk==0 && sqlite3IsRowid(pChanges->a[i].zName) ){
j = -1;
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
pParse->checkSchema = 1;
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
j<0 ? "ROWID" : pTab->aCol[j].zName,
db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
assert( (chngRowid & chngPk)==0 );
assert( chngRowid==0 || chngRowid==1 );
assert( chngPk==0 || chngPk==1 );
chngKey = chngRowid + chngPk;
/* The SET expressions are not actually used inside the WHERE loop.
** So reset the colUsed mask
*/
pTabList->a[0].colUsed = 0;
hasFK = sqlite3FkRequired(pParse, pTab, aXRef, chngKey);
/* There is one entry in the aRegIdx[] array for each index on the table
** being updated. Fill in aRegIdx[] with a register number that will hold
** the key for accessing each index.
*/
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngKey || hasFK || pIdx->pPartIdxWhere || pIdx==pPk ){
reg = ++pParse->nMem;
}else{
reg = 0;
for(i=0; i<pIdx->nKeyCol; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ){
reg = ++pParse->nMem;
break;
}
}
}
if( reg==0 ) aToOpen[j+1] = 0;
aRegIdx[j] = reg;
}
/* Begin generating code. */
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Virtual tables must be handled separately */
if( IsVirtual(pTab) ){
updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
pWhere, onError);
pWhere = 0;
pTabList = 0;
goto update_cleanup;
}
#endif
/* Allocate required registers. */
regRowSet = ++pParse->nMem;
regOldRowid = regNewRowid = ++pParse->nMem;
if( chngPk || pTrigger || hasFK ){
regOld = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
}
if( chngKey || pTrigger || hasFK ){
regNewRowid = ++pParse->nMem;
}
regNew = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
/* Start the view context. */
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* If we are trying to update a view, realize that view into
** a ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iDataCur);
}
#endif
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto update_cleanup;
}
/* Begin the database scan
*/
if( HasRowid(pTab) ){
sqlite3VdbeAddOp3(v, OP_Null, 0, regRowSet, regOldRowid);
pWInfo = sqlite3WhereBegin(
pParse, pTabList, pWhere, 0, 0, WHERE_ONEPASS_DESIRED, iIdxCur
);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
/* Remember the rowid of every item to be updated.
*/
sqlite3VdbeAddOp2(v, OP_Rowid, iDataCur, regOldRowid);
if( !okOnePass ){
sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
}
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
}else{
int iPk; /* First of nPk memory cells holding PRIMARY KEY value */
i16 nPk; /* Number of components of the PRIMARY KEY */
int addrOpen; /* Address of the OpenEphemeral instruction */
assert( pPk!=0 );
nPk = pPk->nKeyCol;
iPk = pParse->nMem+1;
pParse->nMem += nPk;
regKey = ++pParse->nMem;
iEph = pParse->nTab++;
sqlite3VdbeAddOp2(v, OP_Null, 0, iPk);
addrOpen = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEph, nPk);
sqlite3VdbeSetP4KeyInfo(pParse, pPk);
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0,
WHERE_ONEPASS_DESIRED, iIdxCur);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
for(i=0; i<nPk; i++){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, pPk->aiColumn[i],
iPk+i);
}
if( okOnePass ){
sqlite3VdbeChangeToNoop(v, addrOpen);
nKey = nPk;
regKey = iPk;
}else{
sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, regKey,
sqlite3IndexAffinityStr(v, pPk), nPk);
sqlite3VdbeAddOp2(v, OP_IdxInsert, iEph, regKey);
}
sqlite3WhereEnd(pWInfo);
}
/* Initialize the count of updated rows
*/
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab ){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
labelBreak = sqlite3VdbeMakeLabel(v);
if( !isView ){
/*
** Open every index that needs updating. Note that if any
** index could potentially invoke a REPLACE conflict resolution
** action, then we need to open all indices because we might need
** to be deleting some records.
*/
if( onError==OE_Replace ){
memset(aToOpen, 1, nIdx+1);
}else{
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
memset(aToOpen, 1, nIdx+1);
break;
}
}
}
if( okOnePass ){
if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iBaseCur] = 0;
if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iBaseCur] = 0;
}
sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, iBaseCur, aToOpen,
0, 0);
}
/* Top of the update loop */
if( okOnePass ){
if( aToOpen[iDataCur-iBaseCur] ){
assert( pPk!=0 );
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelBreak, regKey, nKey);
VdbeCoverageNeverTaken(v);
}
labelContinue = labelBreak;
sqlite3VdbeAddOp2(v, OP_IsNull, pPk ? regKey : regOldRowid, labelBreak);
VdbeCoverage(v);
}else if( pPk ){
labelContinue = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp2(v, OP_Rewind, iEph, labelBreak); VdbeCoverage(v);
addrTop = sqlite3VdbeAddOp2(v, OP_RowKey, iEph, regKey);
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelContinue, regKey, 0);
VdbeCoverage(v);
}else{
labelContinue = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet, labelBreak,
regOldRowid);
VdbeCoverage(v);
sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, labelContinue, regOldRowid);
VdbeCoverage(v);
}
/* If the record number will change, set register regNewRowid to
** contain the new value. If the record number is not being modified,
** then regNewRowid is the same register as regOldRowid, which is
** already populated. */
assert( chngKey || pTrigger || hasFK || regOldRowid==regNewRowid );
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid); VdbeCoverage(v);
}
/* Compute the old pre-UPDATE content of the row being changed, if that
** information is needed */
if( chngPk || hasFK || pTrigger ){
u32 oldmask = (hasFK ? sqlite3FkOldmask(pParse, pTab) : 0);
oldmask |= sqlite3TriggerColmask(pParse,
pTrigger, pChanges, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onError
);
for(i=0; i<pTab->nCol; i++){
if( oldmask==0xffffffff
|| (i<32 && (oldmask & MASKBIT32(i))!=0)
|| (pTab->aCol[i].colFlags & COLFLAG_PRIMKEY)!=0
){
testcase( oldmask!=0xffffffff && i==31 );
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, i, regOld+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regOld+i);
}
}
if( chngRowid==0 && pPk==0 ){
sqlite3VdbeAddOp2(v, OP_Copy, regOldRowid, regNewRowid);
}
}
/* Populate the array of registers beginning at regNew with the new
** row data. This array is used to check constaints, create the new
** table and index records, and as the values for any new.* references
** made by triggers.
**
** If there are one or more BEFORE triggers, then do not populate the
** registers associated with columns that are (a) not modified by
** this UPDATE statement and (b) not accessed by new.* references. The
** values for registers not modified by the UPDATE must be reloaded from
** the database after the BEFORE triggers are fired anyway (as the trigger
** may have modified them). So not loading those that are not going to
** be used eliminates some redundant opcodes.
*/
newmask = sqlite3TriggerColmask(
pParse, pTrigger, pChanges, 1, TRIGGER_BEFORE, pTab, onError
);
/*sqlite3VdbeAddOp3(v, OP_Null, 0, regNew, regNew+pTab->nCol-1);*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
}else{
j = aXRef[i];
if( j>=0 ){
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regNew+i);
}else if( 0==(tmask&TRIGGER_BEFORE) || i>31 || (newmask & MASKBIT32(i)) ){
/* This branch loads the value of a column that will not be changed
** into a register. This is done if there are no BEFORE triggers, or
** if there are one or more BEFORE triggers that use this value via
** a new.* reference in a trigger program.
*/
testcase( i==31 );
testcase( i==32 );
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, i, regNew+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
}
}
}
/* Fire any BEFORE UPDATE triggers. This happens before constraints are
** verified. One could argue that this is wrong.
*/
if( tmask&TRIGGER_BEFORE ){
sqlite3TableAffinity(v, pTab, regNew);
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_BEFORE, pTab, regOldRowid, onError, labelContinue);
/* The row-trigger may have deleted the row being updated. In this
** case, jump to the next row. No updates or AFTER triggers are
** required. This behavior - what happens when the row being updated
** is deleted or renamed by a BEFORE trigger - is left undefined in the
** documentation.
*/
if( pPk ){
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelContinue,regKey,nKey);
VdbeCoverage(v);
}else{
sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, labelContinue, regOldRowid);
VdbeCoverage(v);
}
/* If it did not delete it, the row-trigger may still have modified
** some of the columns of the row being updated. Load the values for
** all columns not modified by the update statement into their
** registers in case this has happened.
*/
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]<0 && i!=pTab->iPKey ){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, i, regNew+i);
}
}
}
if( !isView ){
int j1 = 0; /* Address of jump instruction */
int bReplace = 0; /* True if REPLACE conflict resolution might happen */
/* Do constraint checks. */
assert( regOldRowid>0 );
sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur,
regNewRowid, regOldRowid, chngKey, onError, labelContinue, &bReplace);
/* Do FK constraint checks. */
if( hasFK ){
sqlite3FkCheck(pParse, pTab, regOldRowid, 0, aXRef, chngKey);
}
/* Delete the index entries associated with the current record. */
if( bReplace || chngKey ){
if( pPk ){
j1 = sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, 0, regKey, nKey);
}else{
j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, 0, regOldRowid);
}
VdbeCoverageNeverTaken(v);
}
sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur, aRegIdx);
/* If changing the record number, delete the old record. */
if( hasFK || chngKey || pPk!=0 ){
sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, 0);
}
if( bReplace || chngKey ){
sqlite3VdbeJumpHere(v, j1);
}
if( hasFK ){
sqlite3FkCheck(pParse, pTab, 0, regNewRowid, aXRef, chngKey);
}
/* Insert the new index entries and the new record. */
sqlite3CompleteInsertion(pParse, pTab, iDataCur, iIdxCur,
regNewRowid, aRegIdx, 1, 0, 0);
/* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
** handle rows (possibly in other tables) that refer via a foreign key
** to the row just updated. */
if( hasFK ){
sqlite3FkActions(pParse, pTab, pChanges, regOldRowid, aXRef, chngKey);
}
}
/* Increment the row counter
*/
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab){
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_AFTER, pTab, regOldRowid, onError, labelContinue);
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
if( okOnePass ){
/* Nothing to do at end-of-loop for a single-pass */
}else if( pPk ){
sqlite3VdbeResolveLabel(v, labelContinue);
sqlite3VdbeAddOp2(v, OP_Next, iEph, addrTop); VdbeCoverage(v);
}else{
sqlite3VdbeAddOp2(v, OP_Goto, 0, labelContinue);
}
sqlite3VdbeResolveLabel(v, labelBreak);
/* Close all tables */
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
assert( aRegIdx );
if( aToOpen[i+1] ){
sqlite3VdbeAddOp2(v, OP_Close, iIdxCur+i, 0);
}
}
if( iDataCur<iIdxCur ) sqlite3VdbeAddOp2(v, OP_Close, iDataCur, 0);
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
/*
** Return the number of rows that were changed. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( (db->flags&SQLITE_CountRows) && !pParse->pTriggerTab && !pParse->nested ){
sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3DbFree(db, aXRef); /* Also frees aRegIdx[] and aToOpen[] */
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
sqlite3ExprDelete(db, pWhere);
return;
}
/*
** This routine is called after all of the trigger actions have been parsed
** in order to complete the process of building the trigger.
*/
void sqlite3FinishTrigger(
Parse *pParse, /* Parser context */
TriggerStep *pStepList, /* The triggered program */
Token *pAll /* Token that describes the complete CREATE TRIGGER */
){
Trigger *pTrig = pParse->pNewTrigger; /* Trigger being finished */
char *zName; /* Name of trigger */
sqlite3 *db = pParse->db; /* The database */
DbFixer sFix;
int iDb; /* Database containing the trigger */
Token nameToken; /* Trigger name for error reporting */
pTrig = pParse->pNewTrigger;
pParse->pNewTrigger = 0;
if( NEVER(pParse->nErr) || !pTrig ) goto triggerfinish_cleanup;
zName = pTrig->name;
iDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
pTrig->step_list = pStepList;
while( pStepList ){
pStepList->pTrig = pTrig;
pStepList = pStepList->pNext;
}
nameToken.z = pTrig->name;
nameToken.n = sqlite3Strlen30(nameToken.z);
if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", &nameToken)
&& sqlite3FixTriggerStep(&sFix, pTrig->step_list) ){
goto triggerfinish_cleanup;
}
/* if we are not initializing, and this trigger is not on a TEMP table,
** build the sqlite_master entry
*/
if( !db->init.busy ){
Vdbe *v;
char *z;
/* Make an entry in the sqlite_master table */
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto triggerfinish_cleanup;
sqlite3BeginWriteOperation(pParse, 0, iDb);
z = sqlite3DbStrNDup(db, (char*)pAll->z, pAll->n);
sqlite3NestedParse(pParse,
"INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')",
db->aDb[iDb].zName, SCHEMA_TABLE(iDb), zName,
pTrig->table, z);
sqlite3DbFree(db, z);
sqlite3ChangeCookie(pParse, iDb);
sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, sqlite3MPrintf(
db, "type='trigger' AND name='%q'", zName), P4_DYNAMIC
);
}
if( db->init.busy ){
Trigger *pLink = pTrig;
Hash *pHash = &db->aDb[iDb].pSchema->trigHash;
pTrig = sqlite3HashInsert(pHash, zName, sqlite3Strlen30(zName), pTrig);
if( pTrig ){
db->mallocFailed = 1;
}else if( pLink->pSchema==pLink->pTabSchema ){
Table *pTab;
int n = sqlite3Strlen30(pLink->table);
pTab = sqlite3HashFind(&pLink->pTabSchema->tblHash, pLink->table, n);
assert( pTab!=0 );
pLink->pNext = pTab->pTrigger;
pTab->pTrigger = pLink;
}
}
triggerfinish_cleanup:
sqlite3DeleteTrigger(db, pTrig);
assert( !pParse->pNewTrigger );
sqlite3DeleteTriggerStep(db, pStepList);
}
/*
** Generate code for a DELETE FROM statement.
**
** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
** \________/ \________________/
** pTabList pWhere
*/
void sqlite3DeleteFrom(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table from which we should delete things */
Expr *pWhere /* The WHERE clause. May be null */
){
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
const char *zDb; /* Name of database holding pTab */
int i; /* Loop counter */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Index *pIdx; /* For looping over indices of the table */
int iTabCur; /* Cursor number for the table */
int iDataCur = 0; /* VDBE cursor for the canonical data source */
int iIdxCur = 0; /* Cursor number of the first index */
int nIdx; /* Number of indices */
sqlite3 *db; /* Main database structure */
AuthContext sContext; /* Authorization context */
NameContext sNC; /* Name context to resolve expressions in */
int iDb; /* Database number */
int memCnt = -1; /* Memory cell used for change counting */
int rcauth; /* Value returned by authorization callback */
int okOnePass; /* True for one-pass algorithm without the FIFO */
int aiCurOnePass[2]; /* The write cursors opened by WHERE_ONEPASS */
u8 *aToOpen = 0; /* Open cursor iTabCur+j if aToOpen[j] is true */
Index *pPk; /* The PRIMARY KEY index on the table */
int iPk = 0; /* First of nPk registers holding PRIMARY KEY value */
i16 nPk = 1; /* Number of columns in the PRIMARY KEY */
int iKey; /* Memory cell holding key of row to be deleted */
i16 nKey; /* Number of memory cells in the row key */
int iEphCur = 0; /* Ephemeral table holding all primary key values */
int iRowSet = 0; /* Register for rowset of rows to delete */
int addrBypass = 0; /* Address of jump over the delete logic */
int addrLoop = 0; /* Top of the delete loop */
int addrDelete = 0; /* Jump directly to the delete logic */
int addrEphOpen = 0; /* Instruction to open the Ephemeral table */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to delete from a view */
Trigger *pTrigger; /* List of table triggers, if required */
#endif
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto delete_from_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to delete. This table has to be
** put in an SrcList structure because some of the subroutines we
** will be calling are designed to work with multiple tables and expect
** an SrcList* parameter instead of just a Table* parameter.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto delete_from_cleanup;
/* Figure out if we have any triggers and if the table being
** deleted from is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
isView = pTab->pSelect!=0;
#else
# define pTrigger 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
/* If pTab is really a view, make sure it has been initialized.
*/
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto delete_from_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
goto delete_from_cleanup;
}
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
zDb = db->aDb[iDb].zName;
rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
if( rcauth==SQLITE_DENY ){
goto delete_from_cleanup;
}
assert(!isView || pTrigger);
/* Assign cursor numbers to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
iTabCur = pTabList->a[0].iCursor = pParse->nTab++;
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
pParse->nTab++;
}
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto delete_from_cleanup;
}
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
/* If we are trying to delete from a view, realize that view into
** an ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iTabCur);
iDataCur = iIdxCur = iTabCur;
}
#endif
/* Resolve the column names in the WHERE clause.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto delete_from_cleanup;
}
/* Initialize the counter of the number of rows deleted, if
** we are counting rows.
*/
if( db->flags & SQLITE_CountRows ){
memCnt = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
}
#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
/* Special case: A DELETE without a WHERE clause deletes everything.
** It is easier just to erase the whole table. Prior to version 3.6.5,
** this optimization caused the row change count (the value returned by
** API function sqlite3_count_changes) to be set incorrectly. */
if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab)
&& 0==sqlite3FkRequired(pParse, pTab, 0, 0)
){
assert( !isView );
sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName);
if( HasRowid(pTab) ){
sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
pTab->zName, P4_STATIC);
}
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
}
}else
#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
{
if( HasRowid(pTab) ){
/* For a rowid table, initialize the RowSet to an empty set */
pPk = 0;
nPk = 1;
iRowSet = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
}else{
/* For a WITHOUT ROWID table, create an ephemeral table used to
** hold all primary keys for rows to be deleted. */
pPk = sqlite3PrimaryKeyIndex(pTab);
assert( pPk!=0 );
nPk = pPk->nKeyCol;
iPk = pParse->nMem+1;
pParse->nMem += nPk;
iEphCur = pParse->nTab++;
addrEphOpen = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEphCur, nPk);
sqlite3VdbeSetP4KeyInfo(pParse, pPk);
}
/* Construct a query to find the rowid or primary key for every row
** to be deleted, based on the WHERE clause.
*/
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0,
WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK,
iTabCur+1);
if( pWInfo==0 ) goto delete_from_cleanup;
okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
/* Keep track of the number of rows to be deleted */
if( db->flags & SQLITE_CountRows ){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
}
/* Extract the rowid or primary key for the current row */
if( pPk ){
for(i=0; i<nPk; i++){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iTabCur,
pPk->aiColumn[i], iPk+i);
}
iKey = iPk;
}else{
iKey = pParse->nMem + 1;
iKey = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iTabCur, iKey, 0);
if( iKey>pParse->nMem ) pParse->nMem = iKey;
}
if( okOnePass ){
/* For ONEPASS, no need to store the rowid/primary-key. There is only
** one, so just keep it in its register(s) and fall through to the
** delete code.
*/
nKey = nPk; /* OP_Found will use an unpacked key */
aToOpen = sqlite3DbMallocRaw(db, nIdx+2);
if( aToOpen==0 ){
sqlite3WhereEnd(pWInfo);
goto delete_from_cleanup;
}
memset(aToOpen, 1, nIdx+1);
aToOpen[nIdx+1] = 0;
if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iTabCur] = 0;
if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iTabCur] = 0;
if( addrEphOpen ) sqlite3VdbeChangeToNoop(v, addrEphOpen);
addrDelete = sqlite3VdbeAddOp0(v, OP_Goto); /* Jump to DELETE logic */
}else if( pPk ){
/* Construct a composite key for the row to be deleted and remember it */
iKey = ++pParse->nMem;
nKey = 0; /* Zero tells OP_Found to use a composite key */
sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
sqlite3IndexAffinityStr(v, pPk), nPk);
sqlite3VdbeAddOp2(v, OP_IdxInsert, iEphCur, iKey);
}else{
/* Get the rowid of the row to be deleted and remember it in the RowSet */
nKey = 1; /* OP_Seek always uses a single rowid */
sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
}
/* End of the WHERE loop */
sqlite3WhereEnd(pWInfo);
if( okOnePass ){
/* Bypass the delete logic below if the WHERE loop found zero rows */
addrBypass = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrBypass);
sqlite3VdbeJumpHere(v, addrDelete);
}
/* Unless this is a view, open cursors for the table we are
** deleting from and all its indices. If this is a view, then the
** only effect this statement has is to fire the INSTEAD OF
** triggers.
*/
if( !isView ){
testcase( IsVirtual(pTab) );
sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, iTabCur, aToOpen,
&iDataCur, &iIdxCur);
assert( pPk || IsVirtual(pTab) || iDataCur==iTabCur );
assert( pPk || IsVirtual(pTab) || iIdxCur==iDataCur+1 );
}
/* Set up a loop over the rowids/primary-keys that were found in the
** where-clause loop above.
*/
if( okOnePass ){
/* Just one row. Hence the top-of-loop is a no-op */
assert( nKey==nPk ); /* OP_Found will use an unpacked key */
assert( !IsVirtual(pTab) );
if( aToOpen[iDataCur-iTabCur] ){
assert( pPk!=0 || pTab->pSelect!=0 );
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, addrBypass, iKey, nKey);
VdbeCoverage(v);
}
}else if( pPk ){
addrLoop = sqlite3VdbeAddOp1(v, OP_Rewind, iEphCur); VdbeCoverage(v);
sqlite3VdbeAddOp2(v, OP_RowKey, iEphCur, iKey);
assert( nKey==0 ); /* OP_Found will use a composite key */
}else{
addrLoop = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, 0, iKey);
VdbeCoverage(v);
assert( nKey==1 );
}
/* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iKey, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, OE_Abort);
sqlite3MayAbort(pParse);
}else
#endif
{
int count = (pParse->nested==0); /* True to count changes */
sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
iKey, nKey, count, OE_Default, okOnePass);
}
/* End of the loop over all rowids/primary-keys. */
if( okOnePass ){
sqlite3VdbeResolveLabel(v, addrBypass);
}else if( pPk ){
sqlite3VdbeAddOp2(v, OP_Next, iEphCur, addrLoop+1); VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addrLoop);
}else{
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrLoop);
sqlite3VdbeJumpHere(v, addrLoop);
}
/* Close the cursors open on the table and its indexes. */
if( !isView && !IsVirtual(pTab) ){
if( !pPk ) sqlite3VdbeAddOp1(v, OP_Close, iDataCur);
for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur + i);
}
}
} /* End non-truncate path */
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
/* Return the number of rows that were deleted. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){
sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC);
}
delete_from_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprDelete(db, pWhere);
sqlite3DbFree(db, aToOpen);
return;
}
/*
** Generate code for an UPDATE of a virtual table.
**
** The strategy is that we create an ephemerial table that contains
** for each row to be changed:
**
** (A) The original rowid of that row.
** (B) The revised rowid for the row. (note1)
** (C) The content of every column in the row.
**
** Then we loop over this ephemeral table and for each row in
** the ephermeral table call VUpdate.
**
** When finished, drop the ephemeral table.
**
** (note1) Actually, if we know in advance that (A) is always the same
** as (B) we only store (A), then duplicate (A) when pulling
** it out of the ephemeral table before calling VUpdate.
*/
static void updateVirtualTable(
Parse *pParse, /* The parsing context */
SrcList *pSrc, /* The virtual table to be modified */
Table *pTab, /* The virtual table */
ExprList *pChanges, /* The columns to change in the UPDATE statement */
Expr *pRowid, /* Expression used to recompute the rowid */
int *aXRef, /* Mapping from columns of pTab to entries in pChanges */
Expr *pWhere, /* WHERE clause of the UPDATE statement */
int onError /* ON CONFLICT strategy */
){
Vdbe *v = pParse->pVdbe; /* Virtual machine under construction */
ExprList *pEList = 0; /* The result set of the SELECT statement */
Select *pSelect = 0; /* The SELECT statement */
Expr *pExpr; /* Temporary expression */
int ephemTab; /* Table holding the result of the SELECT */
int i; /* Loop counter */
int addr; /* Address of top of loop */
int iReg; /* First register in set passed to OP_VUpdate */
sqlite3 *db = pParse->db; /* Database connection */
const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
SelectDest dest;
/* Construct the SELECT statement that will find the new values for
** all updated rows.
*/
pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db, TK_ID, "_rowid_"));
if( pRowid ){
pEList = sqlite3ExprListAppend(pParse, pEList,
sqlite3ExprDup(db, pRowid, 0));
}
assert( pTab->iPKey<0 );
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]>=0 ){
pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr, 0);
}else{
pExpr = sqlite3Expr(db, TK_ID, pTab->aCol[i].zName);
}
pEList = sqlite3ExprListAppend(pParse, pEList, pExpr);
}
pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
/* Create the ephemeral table into which the update results will
** be stored.
*/
assert( v );
ephemTab = pParse->nTab++;
sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
/* fill the ephemeral table
*/
sqlite3SelectDestInit(&dest, SRT_Table, ephemTab);
sqlite3Select(pParse, pSelect, &dest);
/* Generate code to scan the ephemeral table and call VUpdate. */
iReg = ++pParse->nMem;
pParse->nMem += pTab->nCol+1;
addr = sqlite3VdbeAddOp2(v, OP_Rewind, ephemTab, 0); VdbeCoverage(v);
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, 0, iReg);
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, (pRowid?1:0), iReg+1);
for(i=0; i<pTab->nCol; i++){
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i);
}
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError);
sqlite3MayAbort(pParse);
sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1); VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addr);
sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
/* Cleanup */
sqlite3SelectDelete(db, pSelect);
}
/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy"
** command.
*/
void sqlite3AlterRenameTable(
Parse *pParse, /* Parser context. */
SrcList *pSrc, /* The table to rename. */
Token *pName /* The new table name. */
){
int iDb; /* Database that contains the table */
char *zDb; /* Name of database iDb */
Table *pTab; /* Table being renamed */
char *zName = 0; /* NULL-terminated version of pName */
sqlite3 *db = pParse->db; /* Database connection */
int nTabName; /* Number of UTF-8 characters in zTabName */
const char *zTabName; /* Original name of the table */
Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
char *zWhere = 0; /* Where clause to locate temp triggers */
#endif
int isVirtualRename = 0; /* True if this is a v-table with an xRename() */
if( db->mallocFailed ) goto exit_rename_table;
assert( pSrc->nSrc==1 );
assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
if( !pTab ) goto exit_rename_table;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
zDb = db->aDb[iDb].zName;
/* Get a NULL terminated version of the new table name. */
zName = sqlite3NameFromToken(db, pName);
if( !zName ) goto exit_rename_table;
/* Check that a table or index named 'zName' does not already exist
** in database iDb. If so, this is an error.
*/
if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
sqlite3ErrorMsg(pParse,
"there is already another table or index with this name: %s", zName);
goto exit_rename_table;
}
/* Make sure it is not a system table being altered, or a reserved name
** that the table is being renamed to.
*/
if( sqlite3Strlen30(pTab->zName)>6
&& 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7)
){
sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
goto exit_rename_table;
}
if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
goto exit_rename_table;
}
#ifndef SQLITE_OMIT_VIEW
if( pTab->pSelect ){
sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
goto exit_rename_table;
}
#endif
#ifndef SQLITE_OMIT_AUTHORIZATION
/* Invoke the authorization callback. */
if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
goto exit_rename_table;
}
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto exit_rename_table;
}
if( IsVirtual(pTab) && pTab->pMod->pModule->xRename ){
isVirtualRename = 1;
}
#endif
/* Begin a transaction and code the VerifyCookie for database iDb.
** Then modify the schema cookie (since the ALTER TABLE modifies the
** schema). Open a statement transaction if the table is a virtual
** table.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto exit_rename_table;
}
sqlite3BeginWriteOperation(pParse, isVirtualRename, iDb);
sqlite3ChangeCookie(pParse, iDb);
/* If this is a virtual table, invoke the xRename() function if
** one is defined. The xRename() callback will modify the names
** of any resources used by the v-table implementation (including other
** SQLite tables) that are identified by the name of the virtual table.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( isVirtualRename ){
int i = ++pParse->nMem;
sqlite3VdbeAddOp4(v, OP_String8, 0, i, 0, zName, 0);
sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pTab->pVtab, P4_VTAB);
}
#endif
/* figure out how many UTF-8 characters are in zName */
zTabName = pTab->zName;
nTabName = sqlite3Utf8CharLen(zTabName, -1);
/* Modify the sqlite_master table to use the new table name. */
sqlite3NestedParse(pParse,
"UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
"sql = sqlite_rename_table(sql, %Q), "
#else
"sql = CASE "
"WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
"ELSE sqlite_rename_table(sql, %Q) END, "
#endif
"tbl_name = %Q, "
"name = CASE "
"WHEN type='table' THEN %Q "
"WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
"'sqlite_autoindex_' || %Q || substr(name,%d+18) "
"ELSE name END "
"WHERE tbl_name=%Q AND "
"(type='table' OR type='index' OR type='trigger');",
zDb, SCHEMA_TABLE(iDb), zName, zName, zName,
#ifndef SQLITE_OMIT_TRIGGER
zName,
#endif
zName, nTabName, zTabName
);
#ifndef SQLITE_OMIT_AUTOINCREMENT
/* If the sqlite_sequence table exists in this database, then update
** it with the new table name.
*/
if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
sqlite3NestedParse(pParse,
"UPDATE \"%w\".sqlite_sequence set name = %Q WHERE name = %Q",
zDb, zName, pTab->zName);
}
#endif
#ifndef SQLITE_OMIT_TRIGGER
/* If there are TEMP triggers on this table, modify the sqlite_temp_master
** table. Don't do this if the table being ALTERed is itself located in
** the temp database.
*/
if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
sqlite3NestedParse(pParse,
"UPDATE sqlite_temp_master SET "
"sql = sqlite_rename_trigger(sql, %Q), "
"tbl_name = %Q "
"WHERE %s;", zName, zName, zWhere);
sqlite3DbFree(db, zWhere);
}
#endif
/* Drop and reload the internal table schema. */
reloadTableSchema(pParse, pTab, zName);
exit_rename_table:
sqlite3SrcListDelete(db, pSrc);
sqlite3DbFree(db, zName);
}
/*
** The parser calls this routine after the CREATE VIRTUAL TABLE statement
** has been completely parsed.
*/
void sqlite3VtabFinishParse(Parse *pParse, Token *pEnd){
Table *pTab = pParse->pNewTable; /* The table being constructed */
sqlite3 *db = pParse->db; /* The database connection */
if( pTab==0 ) return;
addArgumentToVtab(pParse);
pParse->sArg.z = 0;
if( pTab->nModuleArg<1 ) return;
/* If the CREATE VIRTUAL TABLE statement is being entered for the
** first time (in other words if the virtual table is actually being
** created now instead of just being read out of sqlite_master) then
** do additional initialization work and store the statement text
** in the sqlite_master table.
*/
if( !db->init.busy ){
char *zStmt;
char *zWhere;
int iDb;
Vdbe *v;
/* Compute the complete text of the CREATE VIRTUAL TABLE statement */
if( pEnd ){
pParse->sNameToken.n = (int)(pEnd->z - pParse->sNameToken.z) + pEnd->n;
}
zStmt = sqlite3MPrintf(db, "CREATE VIRTUAL TABLE %T", &pParse->sNameToken);
/* A slot for the record has already been allocated in the
** SQLITE_MASTER table. We just need to update that slot with all
** the information we've collected.
**
** The VM register number pParse->regRowid holds the rowid of an
** entry in the sqlite_master table tht was created for this vtab
** by sqlite3StartTable().
*/
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
sqlite3NestedParse(pParse,
"UPDATE %Q.%s "
"SET type='table', name=%Q, tbl_name=%Q, rootpage=0, sql=%Q "
"WHERE rowid=#%d",
db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
pTab->zName,
pTab->zName,
zStmt,
pParse->regRowid
);
sqlite3DbFree(db, zStmt);
v = sqlite3GetVdbe(pParse);
sqlite3ChangeCookie(pParse, iDb);
sqlite3VdbeAddOp2(v, OP_Expire, 0, 0);
zWhere = sqlite3MPrintf(db, "name='%q' AND type='table'", pTab->zName);
sqlite3VdbeAddParseSchemaOp(v, iDb, zWhere);
sqlite3VdbeAddOp4(v, OP_VCreate, iDb, 0, 0,
pTab->zName, sqlite3Strlen30(pTab->zName) + 1);
}
/* If we are rereading the sqlite_master table create the in-memory
** record of the table. The xConnect() method is not called until
** the first time the virtual table is used in an SQL statement. This
** allows a schema that contains virtual tables to be loaded before
** the required virtual table implementations are registered. */
else {
Table *pOld;
Schema *pSchema = pTab->pSchema;
const char *zName = pTab->zName;
int nName = sqlite3Strlen30(zName);
assert( sqlite3SchemaMutexHeld(db, 0, pSchema) );
pOld = sqlite3HashInsert(&pSchema->tblHash, zName, nName, pTab);
if( pOld ){
db->mallocFailed = 1;
assert( pTab==pOld ); /* Malloc must have failed inside HashInsert() */
return;
}
pParse->pNewTable = 0;
}
}
/*
** Generate code for an UPDATE of a virtual table.
**
** There are two possible strategies - the default and the special
** "onepass" strategy. Onepass is only used if the virtual table
** implementation indicates that pWhere may match at most one row.
**
** The default strategy is to create an ephemeral table that contains
** for each row to be changed:
**
** (A) The original rowid of that row.
** (B) The revised rowid for the row.
** (C) The content of every column in the row.
**
** Then loop through the contents of this ephemeral table executing a
** VUpdate for each row. When finished, drop the ephemeral table.
**
** The "onepass" strategy does not use an ephemeral table. Instead, it
** stores the same values (A, B and C above) in a register array and
** makes a single invocation of VUpdate.
*/
static void updateVirtualTable(
Parse *pParse, /* The parsing context */
SrcList *pSrc, /* The virtual table to be modified */
Table *pTab, /* The virtual table */
ExprList *pChanges, /* The columns to change in the UPDATE statement */
Expr *pRowid, /* Expression used to recompute the rowid */
int *aXRef, /* Mapping from columns of pTab to entries in pChanges */
Expr *pWhere, /* WHERE clause of the UPDATE statement */
int onError /* ON CONFLICT strategy */
){
Vdbe *v = pParse->pVdbe; /* Virtual machine under construction */
int ephemTab; /* Table holding the result of the SELECT */
int i; /* Loop counter */
sqlite3 *db = pParse->db; /* Database connection */
const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
WhereInfo *pWInfo;
int nArg = 2 + pTab->nCol; /* Number of arguments to VUpdate */
int regArg; /* First register in VUpdate arg array */
int regRec; /* Register in which to assemble record */
int regRowid; /* Register for ephem table rowid */
int iCsr = pSrc->a[0].iCursor; /* Cursor used for virtual table scan */
int aDummy[2]; /* Unused arg for sqlite3WhereOkOnePass() */
int eOnePass; /* True to use onepass strategy */
int addr; /* Address of OP_OpenEphemeral */
/* Allocate nArg registers in which to gather the arguments for VUpdate. Then
** create and open the ephemeral table in which the records created from
** these arguments will be temporarily stored. */
assert( v );
ephemTab = pParse->nTab++;
addr= sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, nArg);
regArg = pParse->nMem + 1;
pParse->nMem += nArg;
regRec = ++pParse->nMem;
regRowid = ++pParse->nMem;
/* Start scanning the virtual table */
pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0,0,WHERE_ONEPASS_DESIRED,0);
if( pWInfo==0 ) return;
/* Populate the argument registers. */
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]>=0 ){
sqlite3ExprCode(pParse, pChanges->a[aXRef[i]].pExpr, regArg+2+i);
}else{
sqlite3VdbeAddOp3(v, OP_VColumn, iCsr, i, regArg+2+i);
sqlite3VdbeChangeP5(v, OPFLAG_NOCHNG);/* Enable sqlite3_vtab_nochange() */
}
}
if( HasRowid(pTab) ){
sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg);
if( pRowid ){
sqlite3ExprCode(pParse, pRowid, regArg+1);
}else{
sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg+1);
}
}else{
Index *pPk; /* PRIMARY KEY index */
i16 iPk; /* PRIMARY KEY column */
pPk = sqlite3PrimaryKeyIndex(pTab);
assert( pPk!=0 );
assert( pPk->nKeyCol==1 );
iPk = pPk->aiColumn[0];
sqlite3VdbeAddOp3(v, OP_VColumn, iCsr, iPk, regArg);
sqlite3VdbeAddOp2(v, OP_SCopy, regArg+2+iPk, regArg+1);
}
eOnePass = sqlite3WhereOkOnePass(pWInfo, aDummy);
/* There is no ONEPASS_MULTI on virtual tables */
assert( eOnePass==ONEPASS_OFF || eOnePass==ONEPASS_SINGLE );
if( eOnePass ){
/* If using the onepass strategy, no-op out the OP_OpenEphemeral coded
** above. */
sqlite3VdbeChangeToNoop(v, addr);
sqlite3VdbeAddOp1(v, OP_Close, iCsr);
}else{
/* Create a record from the argument register contents and insert it into
** the ephemeral table. */
sqlite3MultiWrite(pParse);
sqlite3VdbeAddOp3(v, OP_MakeRecord, regArg, nArg, regRec);
#ifdef SQLITE_DEBUG
/* Signal an assert() within OP_MakeRecord that it is allowed to
** accept no-change records with serial_type 10 */
sqlite3VdbeChangeP5(v, OPFLAG_NOCHNG_MAGIC);
#endif
sqlite3VdbeAddOp2(v, OP_NewRowid, ephemTab, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, ephemTab, regRec, regRowid);
}
if( eOnePass==ONEPASS_OFF ){
/* End the virtual table scan */
sqlite3WhereEnd(pWInfo);
/* Begin scannning through the ephemeral table. */
addr = sqlite3VdbeAddOp1(v, OP_Rewind, ephemTab); VdbeCoverage(v);
/* Extract arguments from the current row of the ephemeral table and
** invoke the VUpdate method. */
for(i=0; i<nArg; i++){
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i, regArg+i);
}
}
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, nArg, regArg, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError);
sqlite3MayAbort(pParse);
/* End of the ephemeral table scan. Or, if using the onepass strategy,
** jump to here if the scan visited zero rows. */
if( eOnePass==ONEPASS_OFF ){
sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1); VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addr);
sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
}else{
sqlite3WhereEnd(pWInfo);
}
}
/*
** This procedure generates VDBE code for a single invocation of either the
** sqlite_detach() or sqlite_attach() SQL user functions.
*/
static void codeAttach(
Parse *pParse, /* The parser context */
int type, /* Either SQLITE_ATTACH or SQLITE_DETACH */
FuncDef const *pFunc,/* FuncDef wrapper for detachFunc() or attachFunc() */
Expr *pAuthArg, /* Expression to pass to authorization callback */
Expr *pFilename, /* Name of database file */
Expr *pDbname, /* Name of the database to use internally */
Expr *pKey /* Database key for encryption extension */
){
int rc;
NameContext sName;
Vdbe *v;
sqlite3* db = pParse->db;
int regArgs;
if( pParse->nErr ) goto attach_end;
memset(&sName, 0, sizeof(NameContext));
sName.pParse = pParse;
if(
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pFilename)) ||
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pDbname)) ||
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pKey))
){
goto attach_end;
}
#ifndef SQLITE_OMIT_AUTHORIZATION
if( pAuthArg ){
char *zAuthArg;
if( pAuthArg->op==TK_STRING ){
zAuthArg = pAuthArg->u.zToken;
}else{
zAuthArg = 0;
}
rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
if(rc!=SQLITE_OK ){
goto attach_end;
}
}
#endif /* SQLITE_OMIT_AUTHORIZATION */
v = sqlite3GetVdbe(pParse);
regArgs = sqlite3GetTempRange(pParse, 4);
sqlite3ExprCode(pParse, pFilename, regArgs);
sqlite3ExprCode(pParse, pDbname, regArgs+1);
sqlite3ExprCode(pParse, pKey, regArgs+2);
assert( v || db->mallocFailed );
if( v ){
sqlite3VdbeAddOp4(v, OP_Function0, 0, regArgs+3-pFunc->nArg, regArgs+3,
(char *)pFunc, P4_FUNCDEF);
assert( pFunc->nArg==-1 || (pFunc->nArg&0xff)==pFunc->nArg );
sqlite3VdbeChangeP5(v, (u8)(pFunc->nArg));
/* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
** statement only). For DETACH, set it to false (expire all existing
** statements).
*/
sqlite3VdbeAddOp1(v, OP_Expire, (type==SQLITE_ATTACH));
}
attach_end:
sqlite3ExprDelete(db, pFilename);
sqlite3ExprDelete(db, pDbname);
sqlite3ExprDelete(db, pKey);
}
/*
** Process an UPDATE statement.
**
** UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
** \_______/ \________/ \______/ \________________/
* onError pTabList pChanges pWhere
*/
void sqlite3Update(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table in which we should change things */
ExprList *pChanges, /* Things to be changed */
Expr *pWhere, /* The WHERE clause. May be null */
int onError, /* How to handle constraint errors */
ExprList *pOrderBy, /* ORDER BY clause. May be null */
Expr *pLimit, /* LIMIT clause. May be null */
Upsert *pUpsert /* ON CONFLICT clause, or null */
){
int i, j; /* Loop counters */
Table *pTab; /* The table to be updated */
int addrTop = 0; /* VDBE instruction address of the start of the loop */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Vdbe *v; /* The virtual database engine */
Index *pIdx; /* For looping over indices */
Index *pPk; /* The PRIMARY KEY index for WITHOUT ROWID tables */
int nIdx; /* Number of indices that need updating */
int iBaseCur; /* Base cursor number */
int iDataCur; /* Cursor for the canonical data btree */
int iIdxCur; /* Cursor for the first index */
sqlite3 *db; /* The database structure */
int *aRegIdx = 0; /* First register in array assigned to each index */
int *aXRef = 0; /* aXRef[i] is the index in pChanges->a[] of the
** an expression for the i-th column of the table.
** aXRef[i]==-1 if the i-th column is not changed. */
u8 *aToOpen; /* 1 for tables and indices to be opened */
u8 chngPk; /* PRIMARY KEY changed in a WITHOUT ROWID table */
u8 chngRowid; /* Rowid changed in a normal table */
u8 chngKey; /* Either chngPk or chngRowid */
Expr *pRowidExpr = 0; /* Expression defining the new record number */
AuthContext sContext; /* The authorization context */
NameContext sNC; /* The name-context to resolve expressions in */
int iDb; /* Database containing the table being updated */
int eOnePass; /* ONEPASS_XXX value from where.c */
int hasFK; /* True if foreign key processing is required */
int labelBreak; /* Jump here to break out of UPDATE loop */
int labelContinue; /* Jump here to continue next step of UPDATE loop */
int flags; /* Flags for sqlite3WhereBegin() */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True when updating a view (INSTEAD OF trigger) */
Trigger *pTrigger; /* List of triggers on pTab, if required */
int tmask; /* Mask of TRIGGER_BEFORE|TRIGGER_AFTER */
#endif
int newmask; /* Mask of NEW.* columns accessed by BEFORE triggers */
int iEph = 0; /* Ephemeral table holding all primary key values */
int nKey = 0; /* Number of elements in regKey for WITHOUT ROWID */
int aiCurOnePass[2]; /* The write cursors opened by WHERE_ONEPASS */
int addrOpen = 0; /* Address of OP_OpenEphemeral */
int iPk = 0; /* First of nPk cells holding PRIMARY KEY value */
i16 nPk = 0; /* Number of components of the PRIMARY KEY */
int bReplace = 0; /* True if REPLACE conflict resolution might happen */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid = 0; /* The old rowid */
int regNewRowid = 0; /* The new rowid */
int regNew = 0; /* Content of the NEW.* table in triggers */
int regOld = 0; /* Content of OLD.* table in triggers */
int regRowSet = 0; /* Rowset of rows to be updated */
int regKey = 0; /* composite PRIMARY KEY value */
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto update_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to update.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
/* Figure out if we have any triggers and if the table being
** updated is a view.
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges, &tmask);
isView = pTab->pSelect!=0;
assert( pTrigger || tmask==0 );
#else
# define pTrigger 0
# define isView 0
# define tmask 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
#ifdef SQLITE_ENABLE_UPDATE_DELETE_LIMIT
if( !isView ){
pWhere = sqlite3LimitWhere(
pParse, pTabList, pWhere, pOrderBy, pLimit, "UPDATE"
);
pOrderBy = 0;
pLimit = 0;
}
#endif
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, tmask) ){
goto update_cleanup;
}
/* Allocate a cursors for the main database table and for all indices.
** The index cursors might not be used, but if they are used they
** need to occur right after the database cursor. So go ahead and
** allocate enough space, just in case.
*/
iBaseCur = iDataCur = pParse->nTab++;
iIdxCur = iDataCur+1;
pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
testcase( pPk!=0 && pPk!=pTab->pIndex );
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
if( pPk==pIdx ){
iDataCur = pParse->nTab;
}
pParse->nTab++;
}
if( pUpsert ){
/* On an UPSERT, reuse the same cursors already opened by INSERT */
iDataCur = pUpsert->iDataCur;
iIdxCur = pUpsert->iIdxCur;
pParse->nTab = iBaseCur;
}
pTabList->a[0].iCursor = iDataCur;
/* Allocate space for aXRef[], aRegIdx[], and aToOpen[].
** Initialize aXRef[] and aToOpen[] to their default values.
*/
aXRef = sqlite3DbMallocRawNN(db, sizeof(int) * (pTab->nCol+nIdx) + nIdx+2 );
if( aXRef==0 ) goto update_cleanup;
aRegIdx = aXRef+pTab->nCol;
aToOpen = (u8*)(aRegIdx+nIdx);
memset(aToOpen, 1, nIdx+1);
aToOpen[nIdx+1] = 0;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* Initialize the name-context */
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
sNC.uNC.pUpsert = pUpsert;
sNC.ncFlags = NC_UUpsert;
/* Resolve the column names in all the expressions of the
** of the UPDATE statement. Also find the column index
** for each column to be updated in the pChanges array. For each
** column to be updated, make sure we have authorization to change
** that column.
*/
chngRowid = chngPk = 0;
for(i=0; i<pChanges->nExpr; i++){
if( sqlite3ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
goto update_cleanup;
}
for(j=0; j<pTab->nCol; j++){
if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
if( j==pTab->iPKey ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else if( pPk && (pTab->aCol[j].colFlags & COLFLAG_PRIMKEY)!=0 ){
chngPk = 1;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( pPk==0 && sqlite3IsRowid(pChanges->a[i].zName) ){
j = -1;
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
pParse->checkSchema = 1;
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
j<0 ? "ROWID" : pTab->aCol[j].zName,
db->aDb[iDb].zDbSName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
assert( (chngRowid & chngPk)==0 );
assert( chngRowid==0 || chngRowid==1 );
assert( chngPk==0 || chngPk==1 );
chngKey = chngRowid + chngPk;
/* The SET expressions are not actually used inside the WHERE loop.
** So reset the colUsed mask. Unless this is a virtual table. In that
** case, set all bits of the colUsed mask (to ensure that the virtual
** table implementation makes all columns available).
*/
pTabList->a[0].colUsed = IsVirtual(pTab) ? ALLBITS : 0;
hasFK = sqlite3FkRequired(pParse, pTab, aXRef, chngKey);
/* There is one entry in the aRegIdx[] array for each index on the table
** being updated. Fill in aRegIdx[] with a register number that will hold
** the key for accessing each index.
*/
if( onError==OE_Replace ) bReplace = 1;
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngKey || hasFK>1 || pIdx==pPk
|| indexWhereClauseMightChange(pIdx,aXRef,chngRowid)
){
reg = ++pParse->nMem;
pParse->nMem += pIdx->nColumn;
}else{
reg = 0;
for(i=0; i<pIdx->nKeyCol; i++){
if( indexColumnIsBeingUpdated(pIdx, i, aXRef, chngRowid) ){
reg = ++pParse->nMem;
pParse->nMem += pIdx->nColumn;
if( onError==OE_Default && pIdx->onError==OE_Replace ){
bReplace = 1;
}
break;
}
}
}
if( reg==0 ) aToOpen[j+1] = 0;
aRegIdx[j] = reg;
}
if( bReplace ){
/* If REPLACE conflict resolution might be invoked, open cursors on all
** indexes in case they are needed to delete records. */
memset(aToOpen, 1, nIdx+1);
}
/* Begin generating code. */
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, pTrigger || hasFK, iDb);
/* Allocate required registers. */
if( !IsVirtual(pTab) ){
regRowSet = ++pParse->nMem;
regOldRowid = regNewRowid = ++pParse->nMem;
if( chngPk || pTrigger || hasFK ){
regOld = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
}
if( chngKey || pTrigger || hasFK ){
regNewRowid = ++pParse->nMem;
}
regNew = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
}
/* Start the view context. */
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* If we are trying to update a view, realize that view into
** an ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab,
pWhere, pOrderBy, pLimit, iDataCur
);
pOrderBy = 0;
pLimit = 0;
}
#endif
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto update_cleanup;
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Virtual tables must be handled separately */
if( IsVirtual(pTab) ){
updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
pWhere, onError);
goto update_cleanup;
}
#endif
/* Jump to labelBreak to abandon further processing of this UPDATE */
labelContinue = labelBreak = sqlite3VdbeMakeLabel(pParse);
/* Not an UPSERT. Normal processing. Begin by
** initialize the count of updated rows */
if( (db->flags&SQLITE_CountRows)!=0
&& !pParse->pTriggerTab
&& !pParse->nested
&& pUpsert==0
){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
if( HasRowid(pTab) ){
sqlite3VdbeAddOp3(v, OP_Null, 0, regRowSet, regOldRowid);
}else{
assert( pPk!=0 );
nPk = pPk->nKeyCol;
iPk = pParse->nMem+1;
pParse->nMem += nPk;
regKey = ++pParse->nMem;
if( pUpsert==0 ){
iEph = pParse->nTab++;
sqlite3VdbeAddOp3(v, OP_Null, 0, iPk, iPk+nPk-1);
addrOpen = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEph, nPk);
sqlite3VdbeSetP4KeyInfo(pParse, pPk);
}
}
if( pUpsert ){
/* If this is an UPSERT, then all cursors have already been opened by
** the outer INSERT and the data cursor should be pointing at the row
** that is to be updated. So bypass the code that searches for the
** row(s) to be updated.
*/
pWInfo = 0;
eOnePass = ONEPASS_SINGLE;
sqlite3ExprIfFalse(pParse, pWhere, labelBreak, SQLITE_JUMPIFNULL);
}else{
/* Begin the database scan.
**
** Do not consider a single-pass strategy for a multi-row update if
** there are any triggers or foreign keys to process, or rows may
** be deleted as a result of REPLACE conflict handling. Any of these
** things might disturb a cursor being used to scan through the table
** or index, causing a single-pass approach to malfunction. */
flags = WHERE_ONEPASS_DESIRED|WHERE_SEEK_UNIQ_TABLE;
if( !pParse->nested && !pTrigger && !hasFK && !chngKey && !bReplace ){
flags |= WHERE_ONEPASS_MULTIROW;
}
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0, flags, iIdxCur);
if( pWInfo==0 ) goto update_cleanup;
/* A one-pass strategy that might update more than one row may not
** be used if any column of the index used for the scan is being
** updated. Otherwise, if there is an index on "b", statements like
** the following could create an infinite loop:
**
** UPDATE t1 SET b=b+1 WHERE b>?
**
** Fall back to ONEPASS_OFF if where.c has selected a ONEPASS_MULTI
** strategy that uses an index for which one or more columns are being
** updated. */
eOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
if( eOnePass!=ONEPASS_SINGLE ){
sqlite3MultiWrite(pParse);
if( eOnePass==ONEPASS_MULTI ){
int iCur = aiCurOnePass[1];
if( iCur>=0 && iCur!=iDataCur && aToOpen[iCur-iBaseCur] ){
eOnePass = ONEPASS_OFF;
}
assert( iCur!=iDataCur || !HasRowid(pTab) );
}
}
}
if( HasRowid(pTab) ){
/* Read the rowid of the current row of the WHERE scan. In ONEPASS_OFF
** mode, write the rowid into the FIFO. In either of the one-pass modes,
** leave it in register regOldRowid. */
sqlite3VdbeAddOp2(v, OP_Rowid, iDataCur, regOldRowid);
if( eOnePass==ONEPASS_OFF ){
sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
}
}else{
/* Read the PK of the current row into an array of registers. In
** ONEPASS_OFF mode, serialize the array into a record and store it in
** the ephemeral table. Or, in ONEPASS_SINGLE or MULTI mode, change
** the OP_OpenEphemeral instruction to a Noop (the ephemeral table
** is not required) and leave the PK fields in the array of registers. */
for(i=0; i<nPk; i++){
assert( pPk->aiColumn[i]>=0 );
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur,pPk->aiColumn[i],iPk+i);
}
if( eOnePass ){
if( addrOpen ) sqlite3VdbeChangeToNoop(v, addrOpen);
nKey = nPk;
regKey = iPk;
}else{
sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, regKey,
sqlite3IndexAffinityStr(db, pPk), nPk);
sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iEph, regKey, iPk, nPk);
}
}
if( pUpsert==0 ){
if( eOnePass!=ONEPASS_MULTI ){
sqlite3WhereEnd(pWInfo);
}
if( !isView ){
int addrOnce = 0;
/* Open every index that needs updating. */
if( eOnePass!=ONEPASS_OFF ){
if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iBaseCur] = 0;
if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iBaseCur] = 0;
}
if( eOnePass==ONEPASS_MULTI && (nIdx-(aiCurOnePass[1]>=0))>0 ){
addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
}
sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, 0, iBaseCur,
aToOpen, 0, 0);
if( addrOnce ) sqlite3VdbeJumpHere(v, addrOnce);
}
/* Top of the update loop */
if( eOnePass!=ONEPASS_OFF ){
if( !isView && aiCurOnePass[0]!=iDataCur && aiCurOnePass[1]!=iDataCur ){
assert( pPk );
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelBreak, regKey,nKey);
VdbeCoverage(v);
}
if( eOnePass!=ONEPASS_SINGLE ){
labelContinue = sqlite3VdbeMakeLabel(pParse);
}
sqlite3VdbeAddOp2(v, OP_IsNull, pPk ? regKey : regOldRowid, labelBreak);
VdbeCoverageIf(v, pPk==0);
VdbeCoverageIf(v, pPk!=0);
}else if( pPk ){
labelContinue = sqlite3VdbeMakeLabel(pParse);
sqlite3VdbeAddOp2(v, OP_Rewind, iEph, labelBreak); VdbeCoverage(v);
addrTop = sqlite3VdbeAddOp2(v, OP_RowData, iEph, regKey);
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelContinue, regKey, 0);
VdbeCoverage(v);
}else{
labelContinue = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet,labelBreak,
regOldRowid);
VdbeCoverage(v);
sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, labelContinue, regOldRowid);
VdbeCoverage(v);
}
}
/* If the rowid value will change, set register regNewRowid to
** contain the new value. If the rowid is not being modified,
** then regNewRowid is the same register as regOldRowid, which is
** already populated. */
assert( chngKey || pTrigger || hasFK || regOldRowid==regNewRowid );
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid); VdbeCoverage(v);
}
/* Compute the old pre-UPDATE content of the row being changed, if that
** information is needed */
if( chngPk || hasFK || pTrigger ){
u32 oldmask = (hasFK ? sqlite3FkOldmask(pParse, pTab) : 0);
oldmask |= sqlite3TriggerColmask(pParse,
pTrigger, pChanges, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onError
);
for(i=0; i<pTab->nCol; i++){
if( oldmask==0xffffffff
|| (i<32 && (oldmask & MASKBIT32(i))!=0)
|| (pTab->aCol[i].colFlags & COLFLAG_PRIMKEY)!=0
){
testcase( oldmask!=0xffffffff && i==31 );
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, i, regOld+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regOld+i);
}
}
if( chngRowid==0 && pPk==0 ){
sqlite3VdbeAddOp2(v, OP_Copy, regOldRowid, regNewRowid);
}
}
/* Populate the array of registers beginning at regNew with the new
** row data. This array is used to check constants, create the new
** table and index records, and as the values for any new.* references
** made by triggers.
**
** If there are one or more BEFORE triggers, then do not populate the
** registers associated with columns that are (a) not modified by
** this UPDATE statement and (b) not accessed by new.* references. The
** values for registers not modified by the UPDATE must be reloaded from
** the database after the BEFORE triggers are fired anyway (as the trigger
** may have modified them). So not loading those that are not going to
** be used eliminates some redundant opcodes.
*/
newmask = sqlite3TriggerColmask(
pParse, pTrigger, pChanges, 1, TRIGGER_BEFORE, pTab, onError
);
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
}else{
j = aXRef[i];
if( j>=0 ){
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regNew+i);
}else if( 0==(tmask&TRIGGER_BEFORE) || i>31 || (newmask & MASKBIT32(i)) ){
/* This branch loads the value of a column that will not be changed
** into a register. This is done if there are no BEFORE triggers, or
** if there are one or more BEFORE triggers that use this value via
** a new.* reference in a trigger program.
*/
testcase( i==31 );
testcase( i==32 );
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, i, regNew+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
}
}
}
/* Fire any BEFORE UPDATE triggers. This happens before constraints are
** verified. One could argue that this is wrong.
*/
if( tmask&TRIGGER_BEFORE ){
sqlite3TableAffinity(v, pTab, regNew);
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_BEFORE, pTab, regOldRowid, onError, labelContinue);
/* The row-trigger may have deleted the row being updated. In this
** case, jump to the next row. No updates or AFTER triggers are
** required. This behavior - what happens when the row being updated
** is deleted or renamed by a BEFORE trigger - is left undefined in the
** documentation.
*/
if( pPk ){
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelContinue,regKey,nKey);
VdbeCoverage(v);
}else{
sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, labelContinue, regOldRowid);
VdbeCoverage(v);
}
/* After-BEFORE-trigger-reload-loop:
** If it did not delete it, the BEFORE trigger may still have modified
** some of the columns of the row being updated. Load the values for
** all columns not modified by the update statement into their registers
** in case this has happened. Only unmodified columns are reloaded.
** The values computed for modified columns use the values before the
** BEFORE trigger runs. See test case trigger1-18.0 (added 2018-04-26)
** for an example.
*/
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]<0 && i!=pTab->iPKey ){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, i, regNew+i);
}
}
}
if( !isView ){
int addr1 = 0; /* Address of jump instruction */
/* Do constraint checks. */
assert( regOldRowid>0 );
sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur,
regNewRowid, regOldRowid, chngKey, onError, labelContinue, &bReplace,
aXRef, 0);
/* Do FK constraint checks. */
if( hasFK ){
sqlite3FkCheck(pParse, pTab, regOldRowid, 0, aXRef, chngKey);
}
/* Delete the index entries associated with the current record. */
if( bReplace || chngKey ){
if( pPk ){
addr1 = sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, 0, regKey, nKey);
}else{
addr1 = sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, 0, regOldRowid);
}
VdbeCoverageNeverTaken(v);
}
sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur, aRegIdx, -1);
/* If changing the rowid value, or if there are foreign key constraints
** to process, delete the old record. Otherwise, add a noop OP_Delete
** to invoke the pre-update hook.
**
** That (regNew==regnewRowid+1) is true is also important for the
** pre-update hook. If the caller invokes preupdate_new(), the returned
** value is copied from memory cell (regNewRowid+1+iCol), where iCol
** is the column index supplied by the user.
*/
assert( regNew==regNewRowid+1 );
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
sqlite3VdbeAddOp3(v, OP_Delete, iDataCur,
OPFLAG_ISUPDATE | ((hasFK>1 || chngKey) ? 0 : OPFLAG_ISNOOP),
regNewRowid
);
if( eOnePass==ONEPASS_MULTI ){
assert( hasFK==0 && chngKey==0 );
sqlite3VdbeChangeP5(v, OPFLAG_SAVEPOSITION);
}
if( !pParse->nested ){
sqlite3VdbeAppendP4(v, pTab, P4_TABLE);
}
#else
if( hasFK>1 || chngKey ){
sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, 0);
}
#endif
if( bReplace || chngKey ){
sqlite3VdbeJumpHere(v, addr1);
}
if( hasFK ){
sqlite3FkCheck(pParse, pTab, 0, regNewRowid, aXRef, chngKey);
}
/* Insert the new index entries and the new record. */
sqlite3CompleteInsertion(
pParse, pTab, iDataCur, iIdxCur, regNewRowid, aRegIdx,
OPFLAG_ISUPDATE | (eOnePass==ONEPASS_MULTI ? OPFLAG_SAVEPOSITION : 0),
0, 0
);
/* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
** handle rows (possibly in other tables) that refer via a foreign key
** to the row just updated. */
if( hasFK ){
sqlite3FkActions(pParse, pTab, pChanges, regOldRowid, aXRef, chngKey);
}
}
/* Increment the row counter
*/
if( regRowCount ){
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_AFTER, pTab, regOldRowid, onError, labelContinue);
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
if( eOnePass==ONEPASS_SINGLE ){
/* Nothing to do at end-of-loop for a single-pass */
}else if( eOnePass==ONEPASS_MULTI ){
sqlite3VdbeResolveLabel(v, labelContinue);
sqlite3WhereEnd(pWInfo);
}else if( pPk ){
sqlite3VdbeResolveLabel(v, labelContinue);
sqlite3VdbeAddOp2(v, OP_Next, iEph, addrTop); VdbeCoverage(v);
}else{
sqlite3VdbeGoto(v, labelContinue);
}
sqlite3VdbeResolveLabel(v, labelBreak);
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 && pUpsert==0 ){
sqlite3AutoincrementEnd(pParse);
}
/*
** Return the number of rows that were changed, if we are tracking
** that information.
*/
if( regRowCount ){
sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3DbFree(db, aXRef); /* Also frees aRegIdx[] and aToOpen[] */
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
sqlite3ExprDelete(db, pWhere);
#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT)
sqlite3ExprListDelete(db, pOrderBy);
sqlite3ExprDelete(db, pLimit);
#endif
return;
}
/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy"
** command. 生成代码来实现“ALTER TABLE xxx重命名yyy”命令。
*/
void sqlite3AlterRenameTable(
Parse *pParse, /* Parser context. 语法分析器上下文*/
SrcList *pSrc, /* The table to rename. 重命名的表*/
Token *pName /* The new table name. 新表名*/
){
int iDb; /* Database that contains the table 包含表的数据库*/
char *zDb; /* Name of database iDb 数据库iDb 的名称*/
Table *pTab; /* Table being renamed 正在重命名的表*/
char *zName = 0; /* NULL-terminated version of pName pName的空值终止版本*/
sqlite3 *db = pParse->db; /* Database connection 数据库的连接*/
int nTabName; /* Number of UTF-8 characters in zTabName 在 zTabName里的UTF-8类型的数目*/
const char *zTabName; /* Original name of the table 最初的数据库名称*/
Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
char *zWhere = 0; /* Where clause to locate temp triggers Where 子句位于temp触发器*/
#endif
VTable *pVTab = 0; /* Non-zero if this is a v-tab with an xRename() 如果是 一个v-tab 和一个xRename() ，则为零*/
int savedDbFlags; /* Saved value of db->flags db->flags的保留值*/
savedDbFlags = db->flags;
if( NEVER(db->mallocFailed) ) goto exit_rename_table;
assert( pSrc->nSrc==1 );
assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
if( !pTab ) goto exit_rename_table;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
zDb = db->aDb[iDb].zName;
db->flags |= SQLITE_PreferBuiltin;
/* Get a NULL terminated version of the new table name. 得到一个空终止版本的新表的名称。*/
zName = sqlite3NameFromToken(db, pName);
if( !zName ) goto exit_rename_table;
/* Check that a table or index named 'zName' does not already exist
** in database iDb. If so, this is an error.检查一个表或索引名叫“zName”不存在数据库iDb。
如果是这样,这是一个错误。
*/
if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
sqlite3ErrorMsg(pParse,
"there is already another table or index with this name: %s", zName);
goto exit_rename_table;
}
/* Make sure it is not a system table being altered, or a reserved name
** that the table is being renamed to.
确保它不是一个正在被修改的系统表或者一个正在被重命名的保留的名称表
*/
if( SQLITE_OK!=isSystemTable(pParse, pTab->zName) ){
goto exit_rename_table;
}
if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){ goto
exit_rename_table;
}
#ifndef SQLITE_OMIT_VIEW
if( pTab->pSelect ){
sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
goto exit_rename_table;
}
#endif
#ifndef SQLITE_OMIT_AUTHORIZATION
/* Invoke the authorization callback. 调用授权回调。*/
if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
goto exit_rename_table;
}
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto exit_rename_table;
}
if( IsVirtual(pTab) ){
pVTab = sqlite3GetVTable(db, pTab);
if( pVTab->pVtab->pModule->xRename==0 ){
pVTab = 0;
}
}
#endif
/* Begin a transaction and code the VerifyCookie for database iDb.
** Then modify the schema cookie (since the ALTER TABLE modifies the
** schema). Open a statement transaction if the table is a virtual
** table.
对于iDb数据库开始一个事务和代码的VerifyCookie。
然后修改模式cookie(因为ALTER TABLE修改模式)。
如果表是一个虚拟表打开一个声明事务。
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto exit_rename_table;
}
sqlite3BeginWriteOperation(pParse, pVTab!=0, iDb);
sqlite3ChangeCookie(pParse, iDb);
/* If this is a virtual table, invoke the xRename() function if
** one is defined. The xRename() callback will modify the names
** of any resources used by the v-table implementation (including other
** SQLite tables) that are identified by the name of the virtual table.、
如果这是一个虚拟表,调用xRename()函数如果一个定义。
xRename()回调将修改使用v-table实现的任何资源的名字(包括其他SQLite表)，
这个v-table实现是确定的虚拟表的名称。
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( pVTab ){
int i = ++pParse->nMem;
sqlite3VdbeAddOp4(v, OP_String8, 0, i, 0, zName, 0);
sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pVTab, P4_VTAB);
sqlite3MayAbort(pParse);
}
#endif
/* figure out how many UTF-8 characters are in zName 算出在zName里有多少utf - 8字符*/
zTabName = pTab->zName;
nTabName = sqlite3Utf8CharLen(zTabName, -1);
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
if( db->flags&SQLITE_ForeignKeys ){
/* If foreign-key support is enabled, rewrite the CREATE TABLE
** statements corresponding to all child tables of foreign key constraints
** for which the renamed table is the parent table.
如果启用了外键的支持,重写CREATE TABLE语句对应的所有子表的外键约束重命名表的父表。*/
if( (zWhere=whereForeignKeys(pParse, pTab))!=0 ){
sqlite3NestedParse(pParse,
"UPDATE \"%w\".%s SET "
"sql = sqlite_rename_parent(sql, %Q, %Q) "
"WHERE %s;", zDb, SCHEMA_TABLE(iDb), zTabName, zName, zWhere);
sqlite3DbFree(db, zWhere);
}
}
#endif
/* Modify the sqlite_master table to use the new table name. 修改sqlite_master表来使用新的表名。*/
sqlite3NestedParse(pParse,
"UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
"sql = sqlite_rename_table(sql, %Q), "
#else
"sql = CASE "
"WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
"ELSE sqlite_rename_table(sql, %Q) END, "
#endif
"tbl_name = %Q, "
"name = CASE "
"WHEN type='table' THEN %Q "
"WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
"'sqlite_autoindex_' || %Q || substr(name,%d+18) "
"ELSE name END "
"WHERE tbl_name=%Q COLLATE nocase AND "
"(type='table' OR type='index' OR type='trigger');",
zDb, SCHEMA_TABLE(iDb), zName, zName, zName,
#ifndef SQLITE_OMIT_TRIGGER
zName,
#endif
zName, nTabName, zTabName
);
#ifndef SQLITE_OMIT_AUTOINCREMENT
/* If the sqlite_sequence table exists in this database, then update
** it with the new table name.
如果sqlite_sequence表存在于这个数据库中,那么用新表的名称更新它
*/
if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
sqlite3NestedParse(pParse,
"UPDATE \"%w\".sqlite_sequence set name = %Q WHERE name = %Q",
zDb, zName, pTab->zName);
}
#endif
#ifndef SQLITE_OMIT_TRIGGER
/* If there are TEMP triggers on this table, modify the sqlite_temp_master
** table. Don't do this if the table being ALTERed is itself located in
** the temp database.
如果在这个表上有临时触发器，修改sqlite_temp_master表，
如果表被修改本身就是位于临时数据库，不要做这些。
*/
if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
sqlite3NestedParse(pParse,
"UPDATE sqlite_temp_master SET "
"sql = sqlite_rename_trigger(sql, %Q), "
"tbl_name = %Q "
"WHERE %s;", zName, zName, zWhere);
sqlite3DbFree(db, zWhere);
}
#endif
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
if( db->flags&SQLITE_ForeignKeys ){
FKey *p;
for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
Table *pFrom = p->pFrom;
if( pFrom!=pTab ){
reloadTableSchema(pParse, p->pFrom, pFrom->zName);
}
}
}
#endif
/* Drop and reload the internal table schema. 删除和重新加载内部表模式。*/
reloadTableSchema(pParse, pTab, zName);
exit_rename_table:
sqlite3SrcListDelete(db, pSrc);
sqlite3DbFree(db, zName);
db->flags = savedDbFlags;
}
/*
** Generate code for an UPDATE of a virtual table.
**
** There are two possible strategies - the default and the special
** "onepass" strategy. Onepass is only used if the virtual table
** implementation indicates that pWhere may match at most one row.
**
** The default strategy is to create an ephemeral table that contains
** for each row to be changed:
**
** (A) The original rowid of that row.
** (B) The revised rowid for the row.
** (C) The content of every column in the row.
**
** Then loop through the contents of this ephemeral table executing a
** VUpdate for each row. When finished, drop the ephemeral table.
**
** The "onepass" strategy does not use an ephemeral table. Instead, it
** stores the same values (A, B and C above) in a register array and
** makes a single invocation of VUpdate.
*/
static void updateVirtualTable(
Parse *pParse, /* The parsing context */
SrcList *pSrc, /* The virtual table to be modified */
Table *pTab, /* The virtual table */
ExprList *pChanges, /* The columns to change in the UPDATE statement */
Expr *pRowid, /* Expression used to recompute the rowid */
int *aXRef, /* Mapping from columns of pTab to entries in pChanges */
Expr *pWhere, /* WHERE clause of the UPDATE statement */
int onError /* ON CONFLICT strategy */
){
Vdbe *v = pParse->pVdbe; /* Virtual machine under construction */
int ephemTab; /* Table holding the result of the SELECT */
int i; /* Loop counter */
sqlite3 *db = pParse->db; /* Database connection */
const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
WhereInfo *pWInfo;
int nArg = 2 + pTab->nCol; /* Number of arguments to VUpdate */
int regArg; /* First register in VUpdate arg array */
int regRec; /* Register in which to assemble record */
int regRowid; /* Register for ephem table rowid */
int iCsr = pSrc->a[0].iCursor; /* Cursor used for virtual table scan */
int aDummy[2]; /* Unused arg for sqlite3WhereOkOnePass() */
int bOnePass; /* True to use onepass strategy */
int addr; /* Address of OP_OpenEphemeral */
/* Allocate nArg registers to martial the arguments to VUpdate. Then
** create and open the ephemeral table in which the records created from
** these arguments will be temporarily stored. */
assert( v );
ephemTab = pParse->nTab++;
addr= sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, nArg);
regArg = pParse->nMem + 1;
pParse->nMem += nArg;
regRec = ++pParse->nMem;
regRowid = ++pParse->nMem;
/* Start scanning the virtual table */
pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0,0,WHERE_ONEPASS_DESIRED,0);
if( pWInfo==0 ) return;
/* Populate the argument registers. */
sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg);
if( pRowid ){
sqlite3ExprCode(pParse, pRowid, regArg+1);
}else{
sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg+1);
}
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]>=0 ){
sqlite3ExprCode(pParse, pChanges->a[aXRef[i]].pExpr, regArg+2+i);
}else{
sqlite3VdbeAddOp3(v, OP_VColumn, iCsr, i, regArg+2+i);
}
}
bOnePass = sqlite3WhereOkOnePass(pWInfo, aDummy);
if( bOnePass ){
/* If using the onepass strategy, no-op out the OP_OpenEphemeral coded
** above. Also, if this is a top-level parse (not a trigger), clear the
** multi-write flag so that the VM does not open a statement journal */
sqlite3VdbeChangeToNoop(v, addr);
if( sqlite3IsToplevel(pParse) ){
pParse->isMultiWrite = 0;
}
}else{
/* Create a record from the argument register contents and insert it into
** the ephemeral table. */
sqlite3VdbeAddOp3(v, OP_MakeRecord, regArg, nArg, regRec);
sqlite3VdbeAddOp2(v, OP_NewRowid, ephemTab, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, ephemTab, regRec, regRowid);
}
if( bOnePass==0 ){
/* End the virtual table scan */
sqlite3WhereEnd(pWInfo);
/* Begin scannning through the ephemeral table. */
addr = sqlite3VdbeAddOp1(v, OP_Rewind, ephemTab); VdbeCoverage(v);
/* Extract arguments from the current row of the ephemeral table and
** invoke the VUpdate method. */
for(i=0; i<nArg; i++){
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i, regArg+i);
}
}
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, nArg, regArg, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError);
sqlite3MayAbort(pParse);
/* End of the ephemeral table scan. Or, if using the onepass strategy,
** jump to here if the scan visited zero rows. */
if( bOnePass==0 ){
sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1); VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addr);
sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
}else{
sqlite3WhereEnd(pWInfo);
}
}
/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy"
** command.
*/
void sqlite3AlterRenameTable(
Parse *pParse, /* Parser context. */
SrcList *pSrc, /* The table to rename. */
Token *pName /* The new table name. */
){
int iDb; /* Database that contains the table */
char *zDb; /* Name of database iDb */
Table *pTab; /* Table being renamed */
char *zName = 0; /* NULL-terminated version of pName */
sqlite3 *db = pParse->db; /* Database connection */
int nTabName; /* Number of UTF-8 characters in zTabName */
const char *zTabName; /* Original name of the table */
Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
char *zWhere = 0; /* Where clause to locate temp triggers */
#endif
VTable *pVTab = 0; /* Non-zero if this is a v-tab with an xRename() */
int savedDbFlags; /* Saved value of db->flags */
savedDbFlags = db->flags;
if( NEVER(db->mallocFailed) ) goto exit_rename_table;
assert( pSrc->nSrc==1 );
assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
pTab = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]);
if( !pTab ) goto exit_rename_table;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
zDb = db->aDb[iDb].zName;
db->flags |= SQLITE_PreferBuiltin;
/* Get a NULL terminated version of the new table name. */
zName = sqlite3NameFromToken(db, pName);
if( !zName ) goto exit_rename_table;
/* Check that a table or index named 'zName' does not already exist
** in database iDb. If so, this is an error.
*/
if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
sqlite3ErrorMsg(pParse,
"there is already another table or index with this name: %s", zName);
goto exit_rename_table;
}
/* Make sure it is not a system table being altered, or a reserved name
** that the table is being renamed to.
*/
if( SQLITE_OK!=isSystemTable(pParse, pTab->zName) ){
goto exit_rename_table;
}
if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){ goto
exit_rename_table;
}
#ifndef SQLITE_OMIT_VIEW
if( pTab->pSelect ){
sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
goto exit_rename_table;
}
#endif
#ifndef SQLITE_OMIT_AUTHORIZATION
/* Invoke the authorization callback. */
if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
goto exit_rename_table;
}
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto exit_rename_table;
}
if( IsVirtual(pTab) ){
pVTab = sqlite3GetVTable(db, pTab);
if( pVTab->pVtab->pModule->xRename==0 ){
pVTab = 0;
}
}
#endif
/* Begin a transaction for database iDb.
** Then modify the schema cookie (since the ALTER TABLE modifies the
** schema). Open a statement transaction if the table is a virtual
** table.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto exit_rename_table;
}
sqlite3BeginWriteOperation(pParse, pVTab!=0, iDb);
sqlite3ChangeCookie(pParse, iDb);
/* If this is a virtual table, invoke the xRename() function if
** one is defined. The xRename() callback will modify the names
** of any resources used by the v-table implementation (including other
** SQLite tables) that are identified by the name of the virtual table.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( pVTab ){
int i = ++pParse->nMem;
sqlite3VdbeLoadString(v, i, zName);
sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pVTab, P4_VTAB);
sqlite3MayAbort(pParse);
}
#endif
/* figure out how many UTF-8 characters are in zName */
zTabName = pTab->zName;
nTabName = sqlite3Utf8CharLen(zTabName, -1);
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
if( db->flags&SQLITE_ForeignKeys ){
/* If foreign-key support is enabled, rewrite the CREATE TABLE
** statements corresponding to all child tables of foreign key constraints
** for which the renamed table is the parent table. */
if( (zWhere=whereForeignKeys(pParse, pTab))!=0 ){
sqlite3NestedParse(pParse,
"UPDATE \"%w\".%s SET "
"sql = sqlite_rename_parent(sql, %Q, %Q) "
"WHERE %s;", zDb, SCHEMA_TABLE(iDb), zTabName, zName, zWhere);
sqlite3DbFree(db, zWhere);
}
}
#endif
/* Modify the sqlite_master table to use the new table name. */
sqlite3NestedParse(pParse,
"UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
"sql = sqlite_rename_table(sql, %Q), "
#else
"sql = CASE "
"WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
"ELSE sqlite_rename_table(sql, %Q) END, "
#endif
"tbl_name = %Q, "
"name = CASE "
"WHEN type='table' THEN %Q "
"WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
"'sqlite_autoindex_' || %Q || substr(name,%d+18) "
"ELSE name END "
"WHERE tbl_name=%Q COLLATE nocase AND "
"(type='table' OR type='index' OR type='trigger');",
zDb, SCHEMA_TABLE(iDb), zName, zName, zName,
#ifndef SQLITE_OMIT_TRIGGER
zName,
#endif
zName, nTabName, zTabName
);
#ifndef SQLITE_OMIT_AUTOINCREMENT
/* If the sqlite_sequence table exists in this database, then update
** it with the new table name.
*/
if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
sqlite3NestedParse(pParse,
"UPDATE \"%w\".sqlite_sequence set name = %Q WHERE name = %Q",
zDb, zName, pTab->zName);
}
#endif
#ifndef SQLITE_OMIT_TRIGGER
/* If there are TEMP triggers on this table, modify the sqlite_temp_master
** table. Don't do this if the table being ALTERed is itself located in
** the temp database.
*/
if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
sqlite3NestedParse(pParse,
"UPDATE sqlite_temp_master SET "
"sql = sqlite_rename_trigger(sql, %Q), "
"tbl_name = %Q "
"WHERE %s;", zName, zName, zWhere);
sqlite3DbFree(db, zWhere);
}
#endif
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
if( db->flags&SQLITE_ForeignKeys ){
FKey *p;
for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
Table *pFrom = p->pFrom;
if( pFrom!=pTab ){
reloadTableSchema(pParse, p->pFrom, pFrom->zName);
}
}
}
#endif
/* Drop and reload the internal table schema. */
reloadTableSchema(pParse, pTab, zName);
exit_rename_table:
sqlite3SrcListDelete(db, pSrc);
sqlite3DbFree(db, zName);
db->flags = savedDbFlags;
}
/*
** Process a pragma statement.
**
** Pragmas are of this form:
**
** PRAGMA [database.]id [= value]
**
** The identifier might also be a string. The value is a string, and
** identifier, or a number. If minusFlag is true, then the value is
** a number that was preceded by a minus sign.
**
** If the left side is "database.id" then pId1 is the database name
** and pId2 is the id. If the left side is just "id" then pId1 is the
** id and pId2 is any empty string.
*/
void sqlite3Pragma(
Parse *pParse,
Token *pId1, /* First part of [database.]id field */
Token *pId2, /* Second part of [database.]id field, or NULL */
Token *pValue, /* Token for <value>, or NULL */
int minusFlag /* True if a '-' sign preceded <value> */
){
char *zLeft = 0; /* Nul-terminated UTF-8 string <id> */
char *zRight = 0; /* Nul-terminated UTF-8 string <value>, or NULL */
const char *zDb = 0; /* The database name */
Token *pId; /* Pointer to <id> token */
int iDb; /* Database index for <database> */
sqlite3 *db = pParse->db;
Db *pDb;
Vdbe *v = pParse->pVdbe = sqlite3VdbeCreate(db);
if( v==0 ) return;
pParse->nMem = 2;
/* Interpret the [database.] part of the pragma statement. iDb is the
** index of the database this pragma is being applied to in db.aDb[]. */
iDb = sqlite3TwoPartName(pParse, pId1, pId2, &pId);
if( iDb<0 ) return;
pDb = &db->aDb[iDb];
/* If the temp database has been explicitly named as part of the
** pragma, make sure it is open.
*/
if( iDb==1 && sqlite3OpenTempDatabase(pParse) ){
return;
}
zLeft = sqlite3NameFromToken(db, pId);
if( !zLeft ) return;
if( minusFlag ){
zRight = sqlite3MPrintf(db, "-%T", pValue);
}else{
zRight = sqlite3NameFromToken(db, pValue);
}
zDb = ((pId2 && pId2->n>0)?pDb->zName:0);
if( sqlite3AuthCheck(pParse, SQLITE_PRAGMA, zLeft, zRight, zDb) ){
goto pragma_out;
}
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
/*
** PRAGMA [database.]default_cache_size
** PRAGMA [database.]default_cache_size=N
**
** The first form reports the current persistent setting for the
** page cache size. The value returned is the maximum number of
** pages in the page cache. The second form sets both the current
** page cache size value and the persistent page cache size value
** stored in the database file.
**
** The default cache size is stored in meta-value 2 of page 1 of the
** database file. The cache size is actually the absolute value of
** this memory location. The sign of meta-value 2 determines the
** synchronous setting. A negative value means synchronous is off
** and a positive value means synchronous is on.
*/
if( sqlite3StrICmp(zLeft,"default_cache_size")==0 ){
static const VdbeOpList getCacheSize[] = {
{ OP_ReadCookie, 0, 1, 2}, /* 0 */
{ OP_IfPos, 1, 6, 0},
{ OP_Integer, 0, 2, 0},
{ OP_Subtract, 1, 2, 1},
{ OP_IfPos, 1, 6, 0},
{ OP_Integer, 0, 1, 0}, /* 5 */
{ OP_ResultRow, 1, 1, 0},
};
int addr;
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
sqlite3VdbeUsesBtree(v, iDb);
if( !zRight ){
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cache_size", P4_STATIC);
pParse->nMem += 2;
addr = sqlite3VdbeAddOpList(v, ArraySize(getCacheSize), getCacheSize);
sqlite3VdbeChangeP1(v, addr, iDb);
sqlite3VdbeChangeP1(v, addr+5, SQLITE_DEFAULT_CACHE_SIZE);
}else{
int size = atoi(zRight);
if( size<0 ) size = -size;
sqlite3BeginWriteOperation(pParse, 0, iDb);
sqlite3VdbeAddOp2(v, OP_Integer, size, 1);
sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, 2, 2);
addr = sqlite3VdbeAddOp2(v, OP_IfPos, 2, 0);
sqlite3VdbeAddOp2(v, OP_Integer, -size, 1);
sqlite3VdbeJumpHere(v, addr);
sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, 2, 1);
pDb->pSchema->cache_size = size;
sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
}
}else
/*
** PRAGMA [database.]page_size
** PRAGMA [database.]page_size=N
**
** The first form reports the current setting for the
** database page size in bytes. The second form sets the
** database page size value. The value can only be set if
** the database has not yet been created.
*/
if( sqlite3StrICmp(zLeft,"page_size")==0 ){
Btree *pBt = pDb->pBt;
if( !zRight ){
int size = pBt ? sqlite3BtreeGetPageSize(pBt) : 0;
returnSingleInt(pParse, "page_size", size);
}else{
/* Malloc may fail when setting the page-size, as there is an internal
** buffer that the pager module resizes using sqlite3_realloc().
*/
db->nextPagesize = atoi(zRight);
if( SQLITE_NOMEM==sqlite3BtreeSetPageSize(pBt, db->nextPagesize, -1) ){
db->mallocFailed = 1;
}
}
}else
/*
** PRAGMA [database.]max_page_count
** PRAGMA [database.]max_page_count=N
**
** The first form reports the current setting for the
** maximum number of pages in the database file. The
** second form attempts to change this setting. Both
** forms return the current setting.
*/
if( sqlite3StrICmp(zLeft,"max_page_count")==0 ){
Btree *pBt = pDb->pBt;
int newMax = 0;
if( zRight ){
newMax = atoi(zRight);
}
if( pBt ){
newMax = sqlite3BtreeMaxPageCount(pBt, newMax);
}
returnSingleInt(pParse, "max_page_count", newMax);
}else
/*
** PRAGMA [database.]page_count
**
** Return the number of pages in the specified database.
*/
if( sqlite3StrICmp(zLeft,"page_count")==0 ){
Vdbe *v;
int iReg;
v = sqlite3GetVdbe(pParse);
if( !v || sqlite3ReadSchema(pParse) ) goto pragma_out;
sqlite3CodeVerifySchema(pParse, iDb);
iReg = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Pagecount, iDb, iReg);
sqlite3VdbeAddOp2(v, OP_ResultRow, iReg, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "page_count", P4_STATIC);
}else
/*
** PRAGMA [database.]locking_mode
** PRAGMA [database.]locking_mode = (normal|exclusive)
*/
if( sqlite3StrICmp(zLeft,"locking_mode")==0 ){
const char *zRet = "normal";
int eMode = getLockingMode(zRight);
if( pId2->n==0 && eMode==PAGER_LOCKINGMODE_QUERY ){
/* Simple "PRAGMA locking_mode;" statement. This is a query for
** the current default locking mode (which may be different to
** the locking-mode of the main database).
*/
eMode = db->dfltLockMode;
}else{
Pager *pPager;
if( pId2->n==0 ){
/* This indicates that no database name was specified as part
** of the PRAGMA command. In this case the locking-mode must be
** set on all attached databases, as well as the main db file.
**
** Also, the sqlite3.dfltLockMode variable is set so that
** any subsequently attached databases also use the specified
** locking mode.
*/
int ii;
assert(pDb==&db->aDb[0]);
for(ii=2; ii<db->nDb; ii++){
pPager = sqlite3BtreePager(db->aDb[ii].pBt);
sqlite3PagerLockingMode(pPager, eMode);
}
db->dfltLockMode = eMode;
}
pPager = sqlite3BtreePager(pDb->pBt);
eMode = sqlite3PagerLockingMode(pPager, eMode);
}
assert(eMode==PAGER_LOCKINGMODE_NORMAL||eMode==PAGER_LOCKINGMODE_EXCLUSIVE);
if( eMode==PAGER_LOCKINGMODE_EXCLUSIVE ){
zRet = "exclusive";
}
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "locking_mode", P4_STATIC);
sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, zRet, 0);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
}else
/*
** PRAGMA [database.]journal_mode
** PRAGMA [database.]journal_mode = (delete|persist|off)
*/
if( sqlite3StrICmp(zLeft,"journal_mode")==0 ){
int eMode;
static char * const azModeName[] = {"delete", "persist", "off", "truncate"};
if( zRight==0 ){
eMode = PAGER_JOURNALMODE_QUERY;
}else{
int n = strlen(zRight);
eMode = sizeof(azModeName)/sizeof(azModeName[0]) - 1;
while( eMode>=0 && sqlite3StrNICmp(zRight, azModeName[eMode], n)!=0 ){
eMode--;
}
}
if( pId2->n==0 && eMode==PAGER_JOURNALMODE_QUERY ){
/* Simple "PRAGMA journal_mode;" statement. This is a query for
** the current default journal mode (which may be different to
** the journal-mode of the main database).
*/
eMode = db->dfltJournalMode;
}else{
Pager *pPager;
if( pId2->n==0 ){
/* This indicates that no database name was specified as part
** of the PRAGMA command. In this case the journal-mode must be
** set on all attached databases, as well as the main db file.
**
** Also, the sqlite3.dfltJournalMode variable is set so that
** any subsequently attached databases also use the specified
** journal mode.
*/
int ii;
assert(pDb==&db->aDb[0]);
for(ii=1; ii<db->nDb; ii++){
if( db->aDb[ii].pBt ){
pPager = sqlite3BtreePager(db->aDb[ii].pBt);
sqlite3PagerJournalMode(pPager, eMode);
}
}
db->dfltJournalMode = eMode;
}
pPager = sqlite3BtreePager(pDb->pBt);
eMode = sqlite3PagerJournalMode(pPager, eMode);
}
assert( eMode==PAGER_JOURNALMODE_DELETE
|| eMode==PAGER_JOURNALMODE_TRUNCATE
|| eMode==PAGER_JOURNALMODE_PERSIST
|| eMode==PAGER_JOURNALMODE_OFF );
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "journal_mode", P4_STATIC);
sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0,
azModeName[eMode], P4_STATIC);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
}else
/*
** PRAGMA [database.]journal_size_limit
** PRAGMA [database.]journal_size_limit=N
**
** Get or set the (boolean) value of the database 'auto-vacuum' parameter.
*/
if( sqlite3StrICmp(zLeft,"journal_size_limit")==0 ){
Pager *pPager = sqlite3BtreePager(pDb->pBt);
i64 iLimit = -2;
if( zRight ){
int iLimit32 = atoi(zRight);
if( iLimit32<-1 ){
iLimit32 = -1;
}
iLimit = iLimit32;
}
iLimit = sqlite3PagerJournalSizeLimit(pPager, iLimit);
returnSingleInt(pParse, "journal_size_limit", (int)iLimit);
}else
#endif /* SQLITE_OMIT_PAGER_PRAGMAS */
/*
** PRAGMA [database.]auto_vacuum
** PRAGMA [database.]auto_vacuum=N
**
** Get or set the (boolean) value of the database 'auto-vacuum' parameter.
*/
#ifndef SQLITE_OMIT_AUTOVACUUM
if( sqlite3StrICmp(zLeft,"auto_vacuum")==0 ){
Btree *pBt = pDb->pBt;
if( sqlite3ReadSchema(pParse) ){
goto pragma_out;
}
if( !zRight ){
int auto_vacuum =
pBt ? sqlite3BtreeGetAutoVacuum(pBt) : SQLITE_DEFAULT_AUTOVACUUM;
returnSingleInt(pParse, "auto_vacuum", auto_vacuum);
}else{
int eAuto = getAutoVacuum(zRight);
db->nextAutovac = eAuto;
if( eAuto>=0 ){
/* Call SetAutoVacuum() to set initialize the internal auto and
** incr-vacuum flags. This is required in case this connection
** creates the database file. It is important that it is created
** as an auto-vacuum capable db.
*/
int rc = sqlite3BtreeSetAutoVacuum(pBt, eAuto);
if( rc==SQLITE_OK && (eAuto==1 || eAuto==2) ){
/* When setting the auto_vacuum mode to either "full" or
** "incremental", write the value of meta[6] in the database
** file. Before writing to meta[6], check that meta[3] indicates
** that this really is an auto-vacuum capable database.
*/
static const VdbeOpList setMeta6[] = {
{ OP_Transaction, 0, 1, 0}, /* 0 */
{ OP_ReadCookie, 0, 1, 3}, /* 1 */
{ OP_If, 1, 0, 0}, /* 2 */
{ OP_Halt, SQLITE_OK, OE_Abort, 0}, /* 3 */
{ OP_Integer, 0, 1, 0}, /* 4 */
{ OP_SetCookie, 0, 6, 1}, /* 5 */
};
int iAddr;
iAddr = sqlite3VdbeAddOpList(v, ArraySize(setMeta6), setMeta6);
sqlite3VdbeChangeP1(v, iAddr, iDb);
sqlite3VdbeChangeP1(v, iAddr+1, iDb);
sqlite3VdbeChangeP2(v, iAddr+2, iAddr+4);
sqlite3VdbeChangeP1(v, iAddr+4, eAuto-1);
sqlite3VdbeChangeP1(v, iAddr+5, iDb);
sqlite3VdbeUsesBtree(v, iDb);
}
}
}
}else
#endif
/*
** PRAGMA [database.]incremental_vacuum(N)
**
** Do N steps of incremental vacuuming on a database.
*/
#ifndef SQLITE_OMIT_AUTOVACUUM
if( sqlite3StrICmp(zLeft,"incremental_vacuum")==0 ){
int iLimit, addr;
if( sqlite3ReadSchema(pParse) ){
goto pragma_out;
}
if( zRight==0 || !sqlite3GetInt32(zRight, &iLimit) || iLimit<=0 ){
iLimit = 0x7fffffff;
}
sqlite3BeginWriteOperation(pParse, 0, iDb);
sqlite3VdbeAddOp2(v, OP_Integer, iLimit, 1);
addr = sqlite3VdbeAddOp1(v, OP_IncrVacuum, iDb);
sqlite3VdbeAddOp1(v, OP_ResultRow, 1);
sqlite3VdbeAddOp2(v, OP_AddImm, 1, -1);
sqlite3VdbeAddOp2(v, OP_IfPos, 1, addr);
sqlite3VdbeJumpHere(v, addr);
}else
#endif
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
/*
** PRAGMA [database.]cache_size
** PRAGMA [database.]cache_size=N
**
** The first form reports the current local setting for the
** page cache size. The local setting can be different from
** the persistent cache size value that is stored in the database
** file itself. The value returned is the maximum number of
** pages in the page cache. The second form sets the local
** page cache size value. It does not change the persistent
** cache size stored on the disk so the cache size will revert
** to its default value when the database is closed and reopened.
** N should be a positive integer.
*/
if( sqlite3StrICmp(zLeft,"cache_size")==0 ){
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
if( !zRight ){
returnSingleInt(pParse, "cache_size", pDb->pSchema->cache_size);
}else{
int size = atoi(zRight);
if( size<0 ) size = -size;
pDb->pSchema->cache_size = size;
sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
}
}else
/*
** PRAGMA temp_store
** PRAGMA temp_store = "default"|"memory"|"file"
**
** Return or set the local value of the temp_store flag. Changing
** the local value does not make changes to the disk file and the default
** value will be restored the next time the database is opened.
**
** Note that it is possible for the library compile-time options to
** override this setting
*/
if( sqlite3StrICmp(zLeft, "temp_store")==0 ){
if( !zRight ){
returnSingleInt(pParse, "temp_store", db->temp_store);
}else{
changeTempStorage(pParse, zRight);
}
}else
/*
** PRAGMA temp_store_directory
** PRAGMA temp_store_directory = ""|"directory_name"
**
** Return or set the local value of the temp_store_directory flag. Changing
** the value sets a specific directory to be used for temporary files.
** Setting to a null string reverts to the default temporary directory search.
** If temporary directory is changed, then invalidateTempStorage.
**
*/
if( sqlite3StrICmp(zLeft, "temp_store_directory")==0 ){
if( !zRight ){
if( sqlite3_temp_directory ){
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME,
"temp_store_directory", P4_STATIC);
sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, sqlite3_temp_directory, 0);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
}
}else{
#ifndef SQLITE_OMIT_WSD
if( zRight[0] ){
int rc;
int res;
rc = sqlite3OsAccess(db->pVfs, zRight, SQLITE_ACCESS_READWRITE, &res);
if( rc!=SQLITE_OK || res==0 ){
sqlite3ErrorMsg(pParse, "not a writable directory");
goto pragma_out;
}
}
if( SQLITE_TEMP_STORE==0
|| (SQLITE_TEMP_STORE==1 && db->temp_store<=1)
|| (SQLITE_TEMP_STORE==2 && db->temp_store==1)
){
invalidateTempStorage(pParse);
}
sqlite3_free(sqlite3_temp_directory);
if( zRight[0] ){
sqlite3_temp_directory = sqlite3DbStrDup(0, zRight);
}else{
sqlite3_temp_directory = 0;
}
#endif /* SQLITE_OMIT_WSD */
}
}else
/*
** PRAGMA [database.]synchronous
** PRAGMA [database.]synchronous=OFF|ON|NORMAL|FULL
**
** Return or set the local value of the synchronous flag. Changing
** the local value does not make changes to the disk file and the
** default value will be restored the next time the database is
** opened.
*/
if( sqlite3StrICmp(zLeft,"synchronous")==0 ){
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
if( !zRight ){
returnSingleInt(pParse, "synchronous", pDb->safety_level-1);
}else{
if( !db->autoCommit ){
sqlite3ErrorMsg(pParse,
"Safety level may not be changed inside a transaction");
}else{
pDb->safety_level = getSafetyLevel(zRight)+1;
}
}
}else
#endif /* SQLITE_OMIT_PAGER_PRAGMAS */
#ifndef SQLITE_OMIT_FLAG_PRAGMAS
if( flagPragma(pParse, zLeft, zRight) ){
/* The flagPragma() subroutine also generates any necessary code
** there is nothing more to do here */
}else
#endif /* SQLITE_OMIT_FLAG_PRAGMAS */
#ifndef SQLITE_OMIT_SCHEMA_PRAGMAS
/*
** PRAGMA table_info(<table>)
**
** Return a single row for each column of the named table. The columns of
** the returned data set are:
**
** cid: Column id (numbered from left to right, starting at 0)
** name: Column name
** type: Column declaration type.
** notnull: True if 'NOT NULL' is part of column declaration
** dflt_value: The default value for the column, if any.
*/
if( sqlite3StrICmp(zLeft, "table_info")==0 && zRight ){
Table *pTab;
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
pTab = sqlite3FindTable(db, zRight, zDb);
if( pTab ){
int i;
int nHidden = 0;
Column *pCol;
sqlite3VdbeSetNumCols(v, 6);
pParse->nMem = 6;
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cid", P4_STATIC);
sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "type", P4_STATIC);
sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "notnull", P4_STATIC);
sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "dflt_value", P4_STATIC);
sqlite3VdbeSetColName(v, 5, COLNAME_NAME, "pk", P4_STATIC);
sqlite3ViewGetColumnNames(pParse, pTab);
for(i=0, pCol=pTab->aCol; i<pTab->nCol; i++, pCol++){
const Token *pDflt;
if( IsHiddenColumn(pCol) ){
nHidden++;
continue;
}
sqlite3VdbeAddOp2(v, OP_Integer, i-nHidden, 1);
sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pCol->zName, 0);
sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
pCol->zType ? pCol->zType : "", 0);
sqlite3VdbeAddOp2(v, OP_Integer, pCol->notNull, 4);
if( pCol->pDflt && (pDflt = &pCol->pDflt->span)->z ){
sqlite3VdbeAddOp4(v, OP_String8, 0, 5, 0, (char*)pDflt->z, pDflt->n);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, 5);
}
sqlite3VdbeAddOp2(v, OP_Integer, pCol->isPrimKey, 6);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 6);
}
}
}else
if( sqlite3StrICmp(zLeft, "index_info")==0 && zRight ){
Index *pIdx;
Table *pTab;
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
pIdx = sqlite3FindIndex(db, zRight, zDb);
if( pIdx ){
int i;
pTab = pIdx->pTable;
sqlite3VdbeSetNumCols(v, 3);
pParse->nMem = 3;
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seqno", P4_STATIC);
sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "cid", P4_STATIC);
sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "name", P4_STATIC);
for(i=0; i<pIdx->nColumn; i++){
int cnum = pIdx->aiColumn[i];
sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
sqlite3VdbeAddOp2(v, OP_Integer, cnum, 2);
assert( pTab->nCol>cnum );
sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pTab->aCol[cnum].zName, 0);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
}
}
}else
if( sqlite3StrICmp(zLeft, "index_list")==0 && zRight ){
Index *pIdx;
Table *pTab;
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
pTab = sqlite3FindTable(db, zRight, zDb);
if( pTab ){
v = sqlite3GetVdbe(pParse);
pIdx = pTab->pIndex;
if( pIdx ){
int i = 0;
sqlite3VdbeSetNumCols(v, 3);
pParse->nMem = 3;
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P4_STATIC);
sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "unique", P4_STATIC);
while(pIdx){
sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pIdx->zName, 0);
sqlite3VdbeAddOp2(v, OP_Integer, pIdx->onError!=OE_None, 3);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
++i;
pIdx = pIdx->pNext;
}
}
}
}else
if( sqlite3StrICmp(zLeft, "database_list")==0 ){
int i;
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
sqlite3VdbeSetNumCols(v, 3);
pParse->nMem = 3;
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P4_STATIC);
sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "file", P4_STATIC);
for(i=0; i<db->nDb; i++){
if( db->aDb[i].pBt==0 ) continue;
assert( db->aDb[i].zName!=0 );
sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, db->aDb[i].zName, 0);
sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
sqlite3BtreeGetFilename(db->aDb[i].pBt), 0);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
}
}else
if( sqlite3StrICmp(zLeft, "collation_list")==0 ){
int i = 0;
HashElem *p;
sqlite3VdbeSetNumCols(v, 2);
pParse->nMem = 2;
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", P4_STATIC);
sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", P4_STATIC);
for(p=sqliteHashFirst(&db->aCollSeq); p; p=sqliteHashNext(p)){
CollSeq *pColl = (CollSeq *)sqliteHashData(p);
sqlite3VdbeAddOp2(v, OP_Integer, i++, 1);
sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pColl->zName, 0);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
}
}else
#endif /* SQLITE_OMIT_SCHEMA_PRAGMAS */
#ifndef SQLITE_OMIT_FOREIGN_KEY
if( sqlite3StrICmp(zLeft, "foreign_key_list")==0 && zRight ){
FKey *pFK;
Table *pTab;
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
pTab = sqlite3FindTable(db, zRight, zDb);
if( pTab ){
v = sqlite3GetVdbe(pParse);
pFK = pTab->pFKey;
if( pFK ){
int i = 0;
sqlite3VdbeSetNumCols(v, 5);
pParse->nMem = 5;
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "id", P4_STATIC);
sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "seq", P4_STATIC);
sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "table", P4_STATIC);
sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "from", P4_STATIC);
sqlite3VdbeSetColName(v, 4, COLNAME_NAME, "to", P4_STATIC);
while(pFK){
int j;
for(j=0; j<pFK->nCol; j++){
char *zCol = pFK->aCol[j].zCol;
sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
sqlite3VdbeAddOp2(v, OP_Integer, j, 2);
sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pFK->zTo, 0);
sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0,
pTab->aCol[pFK->aCol[j].iFrom].zName, 0);
sqlite3VdbeAddOp4(v, zCol ? OP_String8 : OP_Null, 0, 5, 0, zCol, 0);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 5);
}
++i;
pFK = pFK->pNextFrom;
}
}
}
}else
#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
#ifndef NDEBUG
if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
if( zRight ){
if( getBoolean(zRight) ){
sqlite3ParserTrace(stderr, "parser: ");
}else{
sqlite3ParserTrace(0, 0);
}
}
}else
#endif
/* Reinstall the LIKE and GLOB functions. The variant of LIKE
** used will be case sensitive or not depending on the RHS.
*/
if( sqlite3StrICmp(zLeft, "case_sensitive_like")==0 ){
if( zRight ){
sqlite3RegisterLikeFunctions(db, getBoolean(zRight));
}
}else
#ifndef SQLITE_INTEGRITY_CHECK_ERROR_MAX
# define SQLITE_INTEGRITY_CHECK_ERROR_MAX 100
#endif
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/* Pragma "quick_check" is an experimental reduced version of
** integrity_check designed to detect most database corruption
** without most of the overhead of a full integrity-check.
*/
if( sqlite3StrICmp(zLeft, "integrity_check")==0
|| sqlite3StrICmp(zLeft, "quick_check")==0
){
int i, j, addr, mxErr;
/* Code that appears at the end of the integrity check. If no error
** messages have been generated, output OK. Otherwise output the
** error message
*/
static const VdbeOpList endCode[] = {
{ OP_AddImm, 1, 0, 0}, /* 0 */
{ OP_IfNeg, 1, 0, 0}, /* 1 */
{ OP_String8, 0, 3, 0}, /* 2 */
{ OP_ResultRow, 3, 1, 0},
};
int isQuick = (zLeft[0]=='q');
/* Initialize the VDBE program */
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
pParse->nMem = 6;
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "integrity_check", P4_STATIC);
/* Set the maximum error count */
mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
if( zRight ){
mxErr = atoi(zRight);
if( mxErr<=0 ){
mxErr = SQLITE_INTEGRITY_CHECK_ERROR_MAX;
}
}
sqlite3VdbeAddOp2(v, OP_Integer, mxErr, 1); /* reg[1] holds errors left */
/* Do an integrity check on each database file */
for(i=0; i<db->nDb; i++){
HashElem *x;
Hash *pTbls;
int cnt = 0;
if( OMIT_TEMPDB && i==1 ) continue;
sqlite3CodeVerifySchema(pParse, i);
addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1); /* Halt if out of errors */
sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
sqlite3VdbeJumpHere(v, addr);
/* Do an integrity check of the B-Tree
**
** Begin by filling registers 2, 3, ... with the root pages numbers
** for all tables and indices in the database.
*/
pTbls = &db->aDb[i].pSchema->tblHash;
for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
Table *pTab = sqliteHashData(x);
Index *pIdx;
sqlite3VdbeAddOp2(v, OP_Integer, pTab->tnum, 2+cnt);
cnt++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
sqlite3VdbeAddOp2(v, OP_Integer, pIdx->tnum, 2+cnt);
cnt++;
}
}
if( cnt==0 ) continue;
/* Make sure sufficient number of registers have been allocated */
if( pParse->nMem < cnt+4 ){
pParse->nMem = cnt+4;
}
/* Do the b-tree integrity checks */
sqlite3VdbeAddOp3(v, OP_IntegrityCk, 2, cnt, 1);
sqlite3VdbeChangeP5(v, i);
addr = sqlite3VdbeAddOp1(v, OP_IsNull, 2);
sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
sqlite3MPrintf(db, "*** in database %s ***\n", db->aDb[i].zName),
P4_DYNAMIC);
sqlite3VdbeAddOp3(v, OP_Move, 2, 4, 1);
sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 2);
sqlite3VdbeAddOp2(v, OP_ResultRow, 2, 1);
sqlite3VdbeJumpHere(v, addr);
/* Make sure all the indices are constructed correctly.
*/
for(x=sqliteHashFirst(pTbls); x && !isQuick; x=sqliteHashNext(x)){
Table *pTab = sqliteHashData(x);
Index *pIdx;
int loopTop;
if( pTab->pIndex==0 ) continue;
addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1); /* Stop if out of errors */
sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
sqlite3VdbeJumpHere(v, addr);
sqlite3OpenTableAndIndices(pParse, pTab, 1, OP_OpenRead);
sqlite3VdbeAddOp2(v, OP_Integer, 0, 2); /* reg(2) will count entries */
loopTop = sqlite3VdbeAddOp2(v, OP_Rewind, 1, 0);
sqlite3VdbeAddOp2(v, OP_AddImm, 2, 1); /* increment entry count */
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int jmp2;
static const VdbeOpList idxErr[] = {
{ OP_AddImm, 1, -1, 0},
{ OP_String8, 0, 3, 0}, /* 1 */
{ OP_Rowid, 1, 4, 0},
{ OP_String8, 0, 5, 0}, /* 3 */
{ OP_String8, 0, 6, 0}, /* 4 */
{ OP_Concat, 4, 3, 3},
{ OP_Concat, 5, 3, 3},
{ OP_Concat, 6, 3, 3},
{ OP_ResultRow, 3, 1, 0},
{ OP_IfPos, 1, 0, 0}, /* 9 */
{ OP_Halt, 0, 0, 0},
};
sqlite3GenerateIndexKey(pParse, pIdx, 1, 3, 1);
jmp2 = sqlite3VdbeAddOp3(v, OP_Found, j+2, 0, 3);
addr = sqlite3VdbeAddOpList(v, ArraySize(idxErr), idxErr);
sqlite3VdbeChangeP4(v, addr+1, "rowid ", P4_STATIC);
sqlite3VdbeChangeP4(v, addr+3, " missing from index ", P4_STATIC);
sqlite3VdbeChangeP4(v, addr+4, pIdx->zName, P4_STATIC);
sqlite3VdbeJumpHere(v, addr+9);
sqlite3VdbeJumpHere(v, jmp2);
}
sqlite3VdbeAddOp2(v, OP_Next, 1, loopTop+1);
sqlite3VdbeJumpHere(v, loopTop);
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
static const VdbeOpList cntIdx[] = {
{ OP_Integer, 0, 3, 0},
{ OP_Rewind, 0, 0, 0}, /* 1 */
{ OP_AddImm, 3, 1, 0},
{ OP_Next, 0, 0, 0}, /* 3 */
{ OP_Eq, 2, 0, 3}, /* 4 */
{ OP_AddImm, 1, -1, 0},
{ OP_String8, 0, 2, 0}, /* 6 */
{ OP_String8, 0, 3, 0}, /* 7 */
{ OP_Concat, 3, 2, 2},
{ OP_ResultRow, 2, 1, 0},
};
if( pIdx->tnum==0 ) continue;
addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1);
sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
sqlite3VdbeJumpHere(v, addr);
addr = sqlite3VdbeAddOpList(v, ArraySize(cntIdx), cntIdx);
sqlite3VdbeChangeP1(v, addr+1, j+2);
sqlite3VdbeChangeP2(v, addr+1, addr+4);
sqlite3VdbeChangeP1(v, addr+3, j+2);
sqlite3VdbeChangeP2(v, addr+3, addr+2);
sqlite3VdbeJumpHere(v, addr+4);
sqlite3VdbeChangeP4(v, addr+6,
"wrong # of entries in index ", P4_STATIC);
sqlite3VdbeChangeP4(v, addr+7, pIdx->zName, P4_STATIC);
}
}
}
addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode);
sqlite3VdbeChangeP2(v, addr, -mxErr);
sqlite3VdbeJumpHere(v, addr+1);
sqlite3VdbeChangeP4(v, addr+2, "ok", P4_STATIC);
}else
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
#ifndef SQLITE_OMIT_UTF16
/*
** PRAGMA encoding
** PRAGMA encoding = "utf-8"|"utf-16"|"utf-16le"|"utf-16be"
**
** In its first form, this pragma returns the encoding of the main
** database. If the database is not initialized, it is initialized now.
**
** The second form of this pragma is a no-op if the main database file
** has not already been initialized. In this case it sets the default
** encoding that will be used for the main database file if a new file
** is created. If an existing main database file is opened, then the
** default text encoding for the existing database is used.
**
** In all cases new databases created using the ATTACH command are
** created to use the same default text encoding as the main database. If
** the main database has not been initialized and/or created when ATTACH
** is executed, this is done before the ATTACH operation.
**
** In the second form this pragma sets the text encoding to be used in
** new database files created using this database handle. It is only
** useful if invoked immediately after the main database i
*/
if( sqlite3StrICmp(zLeft, "encoding")==0 ){
static const struct EncName {
char *zName;
u8 enc;
} encnames[] = {
{ "UTF-8", SQLITE_UTF8 },
{ "UTF8", SQLITE_UTF8 },
{ "UTF-16le", SQLITE_UTF16LE },
{ "UTF16le", SQLITE_UTF16LE },
{ "UTF-16be", SQLITE_UTF16BE },
{ "UTF16be", SQLITE_UTF16BE },
{ "UTF-16", 0 }, /* SQLITE_UTF16NATIVE */
{ "UTF16", 0 }, /* SQLITE_UTF16NATIVE */
{ 0, 0 }
};
const struct EncName *pEnc;
if( !zRight ){ /* "PRAGMA encoding" */
if( sqlite3ReadSchema(pParse) ) goto pragma_out;
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "encoding", P4_STATIC);
sqlite3VdbeAddOp2(v, OP_String8, 0, 1);
for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
if( pEnc->enc==ENC(pParse->db) ){
sqlite3VdbeChangeP4(v, -1, pEnc->zName, P4_STATIC);
break;
}
}
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
}else{ /* "PRAGMA encoding = XXX" */
/* Only change the value of sqlite.enc if the database handle is not
** initialized. If the main database exists, the new sqlite.enc value
** will be overwritten when the schema is next loaded. If it does not
** already exists, it will be created to use the new encoding value.
*/
if(
!(DbHasProperty(db, 0, DB_SchemaLoaded)) ||
DbHasProperty(db, 0, DB_Empty)
){
for(pEnc=&encnames[0]; pEnc->zName; pEnc++){
if( 0==sqlite3StrICmp(zRight, pEnc->zName) ){
ENC(pParse->db) = pEnc->enc ? pEnc->enc : SQLITE_UTF16NATIVE;
break;
}
}
if( !pEnc->zName ){
sqlite3ErrorMsg(pParse, "unsupported encoding: %s", zRight);
}
}
}
}else
#endif /* SQLITE_OMIT_UTF16 */
#ifndef SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS
/*
** PRAGMA [database.]schema_version
** PRAGMA [database.]schema_version = <integer>
**
** PRAGMA [database.]user_version
** PRAGMA [database.]user_version = <integer>
**
** The pragma's schema_version and user_version are used to set or get
** the value of the schema-version and user-version, respectively. Both
** the schema-version and the user-version are 32-bit signed integers
** stored in the database header.
**
** The schema-cookie is usually only manipulated internally by SQLite. It
** is incremented by SQLite whenever the database schema is modified (by
** creating or dropping a table or index). The schema version is used by
** SQLite each time a query is executed to ensure that the internal cache
** of the schema used when compiling the SQL query matches the schema of
** the database against which the compiled query is actually executed.
** Subverting this mechanism by using "PRAGMA schema_version" to modify
** the schema-version is potentially dangerous and may lead to program
** crashes or database corruption. Use with caution!
**
** The user-version is not used internally by SQLite. It may be used by
** applications for any purpose.
*/
if( sqlite3StrICmp(zLeft, "schema_version")==0
|| sqlite3StrICmp(zLeft, "user_version")==0
|| sqlite3StrICmp(zLeft, "freelist_count")==0
){
int iCookie; /* Cookie index. 0 for schema-cookie, 6 for user-cookie. */
sqlite3VdbeUsesBtree(v, iDb);
switch( zLeft[0] ){
case 's': case 'S':
iCookie = 0;
break;
case 'f': case 'F':
iCookie = 1;
iDb = (-1*(iDb+1));
assert(iDb<=0);
break;
default:
iCookie = 5;
break;
}
if( zRight && iDb>=0 ){
/* Write the specified cookie value */
static const VdbeOpList setCookie[] = {
{ OP_Transaction, 0, 1, 0}, /* 0 */
{ OP_Integer, 0, 1, 0}, /* 1 */
{ OP_SetCookie, 0, 0, 1}, /* 2 */
};
int addr = sqlite3VdbeAddOpList(v, ArraySize(setCookie), setCookie);
sqlite3VdbeChangeP1(v, addr, iDb);
sqlite3VdbeChangeP1(v, addr+1, atoi(zRight));
sqlite3VdbeChangeP1(v, addr+2, iDb);
sqlite3VdbeChangeP2(v, addr+2, iCookie);
}else{
/* Read the specified cookie value */
static const VdbeOpList readCookie[] = {
{ OP_ReadCookie, 0, 1, 0}, /* 0 */
{ OP_ResultRow, 1, 1, 0}
};
int addr = sqlite3VdbeAddOpList(v, ArraySize(readCookie), readCookie);
sqlite3VdbeChangeP1(v, addr, iDb);
sqlite3VdbeChangeP3(v, addr, iCookie);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLeft, P4_TRANSIENT);
}
}else
#endif /* SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS */
#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
/*
** Report the current state of file logs for all databases
*/
if( sqlite3StrICmp(zLeft, "lock_status")==0 ){
static const char *const azLockName[] = {
"unlocked", "shared", "reserved", "pending", "exclusive"
};
int i;
Vdbe *v = sqlite3GetVdbe(pParse);
sqlite3VdbeSetNumCols(v, 2);
pParse->nMem = 2;
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "database", P4_STATIC);
sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "status", P4_STATIC);
for(i=0; i<db->nDb; i++){
Btree *pBt;
Pager *pPager;
const char *zState = "unknown";
int j;
if( db->aDb[i].zName==0 ) continue;
sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, db->aDb[i].zName, P4_STATIC);
pBt = db->aDb[i].pBt;
if( pBt==0 || (pPager = sqlite3BtreePager(pBt))==0 ){
zState = "closed";
}else if( sqlite3_file_control(db, i ? db->aDb[i].zName : 0,
SQLITE_FCNTL_LOCKSTATE, &j)==SQLITE_OK ){
zState = azLockName[j];
}
sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, zState, P4_STATIC);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 2);
}
}else
#endif
#ifdef SQLITE_SSE
/*
** Check to see if the sqlite_statements table exists. Create it
** if it does not.
*/
if( sqlite3StrICmp(zLeft, "create_sqlite_statement_table")==0 ){
extern int sqlite3CreateStatementsTable(Parse*);
sqlite3CreateStatementsTable(pParse);
}else
#endif
#if SQLITE_HAS_CODEC
if( sqlite3StrICmp(zLeft, "key")==0 ){
sqlite3_key(db, zRight, strlen(zRight));
}else
#endif
#if SQLITE_HAS_CODEC || defined(SQLITE_ENABLE_CEROD)
if( sqlite3StrICmp(zLeft, "activate_extensions")==0 ){
#if SQLITE_HAS_CODEC
if( sqlite3StrNICmp(zRight, "see-", 4)==0 ){
extern void sqlite3_activate_see(const char*);
sqlite3_activate_see(&zRight[4]);
}
#endif
#ifdef SQLITE_ENABLE_CEROD
if( sqlite3StrNICmp(zRight, "cerod-", 6)==0 ){
extern void sqlite3_activate_cerod(const char*);
sqlite3_activate_cerod(&zRight[6]);
}
#endif
}
#endif
{}
if( v ){
/* Code an OP_Expire at the end of each PRAGMA program to cause
** the VDBE implementing the pragma to expire. Most (all?) pragmas
** are only valid for a single execution.
*/
sqlite3VdbeAddOp2(v, OP_Expire, 1, 0);
/*
** Reset the safety level, in case the fullfsync flag or synchronous
** setting changed.
*/
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
if( db->autoCommit ){
sqlite3BtreeSetSafetyLevel(pDb->pBt, pDb->safety_level,
(db->flags&SQLITE_FullFSync)!=0);
}
#endif
}
pragma_out:
sqlite3DbFree(db, zLeft);
sqlite3DbFree(db, zRight);
}