/*
** 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 addr = 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 */
int nIdx; /* Number of indices that need updating */
int nIdxTotal; /* Total number of indices */
int iCur; /* VDBE Cursor number of pTab */
sqlite3 *db; /* The database structure */
Index **apIdx = 0; /* An array of indices that need updating too */
char *aIdxUsed = 0; /* aIdxUsed[i]==1 if the i-th index is used */
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. */
int chngRecno; /* True if the record number is being changed */
Expr *pRecnoExpr = 0; /* Expression defining the new record number */
int openAll = 0; /* True if all indices need to be opened */
AuthContext sContext; /* The authorization context */
NameContext sNC; /* The name-context to resolve expressions in */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* Trying to update a view */
int triggers_exist = 0; /* True if any row triggers exist */
#endif
int newIdx = -1; /* index of trigger "new" temp table */
int oldIdx = -1; /* index of trigger "old" temp table */
sContext.pParse = 0;
if( pParse->nErr || sqlite3_malloc_failed ) goto update_cleanup;
db = pParse->db;
assert( pTabList->nSrc==1 );
/* Locate the table which we want to update.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
/* Figure out if we have any triggers and if the table being
** updated is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges);
isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
goto update_cleanup;
}
if( isView ){
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
}
aXRef = sqliteMallocRaw( sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto update_cleanup;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* If there are FOR EACH ROW triggers, allocate cursors for the
** special OLD and NEW tables
*/
if( triggers_exist ){
newIdx = pParse->nTab++;
oldIdx = pParse->nTab++;
}
/* 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 = iCur = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* 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.
*/
chngRecno = 0;
for(i=0; i<pChanges->nExpr; i++){
if( sqlite3ExprResolveNames(&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 ){
chngRecno = 1;
pRecnoExpr = pChanges->a[i].pExpr;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pChanges->a[i].zName) ){
chngRecno = 1;
pRecnoExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
pTab->aCol[j].zName, db->aDb[pTab->iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
/* Allocate memory for the array apIdx[] and fill it with pointers to every
** index that needs to be updated. Indices only need updating if their
** key includes one of the columns named in pChanges or if the record
** number of the original table entry is changing.
*/
for(nIdx=nIdxTotal=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdxTotal++){
if( chngRecno ){
i = 0;
}else {
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
}
}
if( i<pIdx->nColumn ) nIdx++;
}
if( nIdxTotal>0 ){
apIdx = sqliteMallocRaw( sizeof(Index*) * nIdx + nIdxTotal );
if( apIdx==0 ) goto update_cleanup;
aIdxUsed = (char*)&apIdx[nIdx];
}
for(nIdx=j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
if( chngRecno ){
i = 0;
}else{
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
}
}
if( i<pIdx->nColumn ){
if( sqlite3CheckIndexCollSeq(pParse, pIdx) ) goto update_cleanup;
apIdx[nIdx++] = pIdx;
aIdxUsed[j] = 1;
}else{
aIdxUsed[j] = 0;
}
}
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( sqlite3ExprResolveNames(&sNC, pWhere) ){
goto update_cleanup;
}
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, pTab->iDb);
/* If we are trying to update a view, construct that view into
** a temporary table.
*/
if( isView ){
Select *pView;
pView = sqlite3SelectDup(pTab->pSelect);
sqlite3Select(pParse, pView, SRT_TempTable, iCur, 0, 0, 0, 0);
sqlite3SelectDelete(pView);
}
/* Begin the database scan
*/
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0);
if( pWInfo==0 ) goto update_cleanup;
/* Remember the index of every item to be updated.
*/
sqlite3VdbeAddOp(v, OP_Recno, iCur, 0);
sqlite3VdbeAddOp(v, OP_ListWrite, 0, 0);
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
/* Initialize the count of updated rows
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
sqlite3VdbeAddOp(v, OP_Integer, 0, 0);
}
if( triggers_exist ){
/* Create pseudo-tables for NEW and OLD
*/
sqlite3VdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, oldIdx, pTab->nCol);
sqlite3VdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, newIdx, pTab->nCol);
/* The top of the update loop for when there are triggers.
*/
sqlite3VdbeAddOp(v, OP_ListRewind, 0, 0);
addr = sqlite3VdbeAddOp(v, OP_ListRead, 0, 0);
sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
/* Open a cursor and make it point to the record that is
** being updated.
*/
sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
if( !isView ){
sqlite3OpenTableForReading(v, iCur, pTab);
}
sqlite3VdbeAddOp(v, OP_MoveGe, iCur, 0);
/* Generate the OLD table
*/
sqlite3VdbeAddOp(v, OP_Recno, iCur, 0);
sqlite3VdbeAddOp(v, OP_RowData, iCur, 0);
sqlite3VdbeAddOp(v, OP_PutIntKey, oldIdx, 0);
/* Generate the NEW table
*/
if( chngRecno ){
sqlite3ExprCodeAndCache(pParse, pRecnoExpr);
}else{
sqlite3VdbeAddOp(v, OP_Recno, iCur, 0);
}
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp(v, OP_String8, 0, 0);
continue;
}
j = aXRef[i];
if( j<0 ){
sqlite3VdbeAddOp(v, OP_Column, iCur, i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCodeAndCache(pParse, pChanges->a[j].pExpr);
}
}
sqlite3VdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
if( !isView ){
sqlite3TableAffinityStr(v, pTab);
}
if( pParse->nErr ) goto update_cleanup;
sqlite3VdbeAddOp(v, OP_PutIntKey, newIdx, 0);
if( !isView ){
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}
/* Fire the BEFORE and INSTEAD OF triggers
*/
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_BEFORE, pTab,
newIdx, oldIdx, onError, addr) ){
goto update_cleanup;
}
}
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.
*/
sqlite3VdbeAddOp(v, OP_Integer, pTab->iDb, 0);
sqlite3VdbeAddOp(v, OP_OpenWrite, iCur, pTab->tnum);
sqlite3VdbeAddOp(v, OP_SetNumColumns, iCur, pTab->nCol);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] ){
sqlite3VdbeAddOp(v, OP_Integer, pIdx->iDb, 0);
sqlite3VdbeOp3(v, OP_OpenWrite, iCur+i+1, pIdx->tnum,
(char*)&pIdx->keyInfo, P3_KEYINFO);
assert( pParse->nTab>iCur+i+1 );
}
}
/* Loop over every record that needs updating. We have to load
** the old data for each record to be updated because some columns
** might not change and we will need to copy the old value.
** Also, the old data is needed to delete the old index entires.
** So make the cursor point at the old record.
*/
if( !triggers_exist ){
sqlite3VdbeAddOp(v, OP_ListRewind, 0, 0);
addr = sqlite3VdbeAddOp(v, OP_ListRead, 0, 0);
sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
}
sqlite3VdbeAddOp(v, OP_NotExists, iCur, addr);
/* If the record number will change, push the record number as it
** will be after the update. (The old record number is currently
** on top of the stack.)
*/
if( chngRecno ){
sqlite3ExprCode(pParse, pRecnoExpr);
sqlite3VdbeAddOp(v, OP_MustBeInt, 0, 0);
}
/* Compute new data for this record.
*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp(v, OP_String8, 0, 0);
continue;
}
j = aXRef[i];
if( j<0 ){
sqlite3VdbeAddOp(v, OP_Column, iCur, i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCode(pParse, pChanges->a[j].pExpr);
}
}
/* Do constraint checks
*/
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, aIdxUsed, chngRecno, 1,
onError, addr);
/* Delete the old indices for the current record.
*/
sqlite3GenerateRowIndexDelete(db, v, pTab, iCur, aIdxUsed);
/* If changing the record number, delete the old record.
*/
if( chngRecno ){
sqlite3VdbeAddOp(v, OP_Delete, iCur, 0);
}
/* Create the new index entries and the new record.
*/
sqlite3CompleteInsertion(pParse, pTab, iCur, aIdxUsed, chngRecno, 1, -1);
}
/* Increment the row counter
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack){
sqlite3VdbeAddOp(v, OP_AddImm, 1, 0);
}
/* If there are triggers, close all the cursors after each iteration
** through the loop. The fire the after triggers.
*/
if( triggers_exist ){
if( !isView ){
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] )
sqlite3VdbeAddOp(v, OP_Close, iCur+i+1, 0);
}
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_AFTER, pTab,
newIdx, oldIdx, onError, addr) ){
goto update_cleanup;
}
}
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
sqlite3VdbeAddOp(v, OP_Goto, 0, addr);
sqlite3VdbeChangeP2(v, addr, sqlite3VdbeCurrentAddr(v));
sqlite3VdbeAddOp(v, OP_ListReset, 0, 0);
/* Close all tables if there were no FOR EACH ROW triggers */
if( !triggers_exist ){
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] ){
sqlite3VdbeAddOp(v, OP_Close, iCur+i+1, 0);
}
}
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}else{
sqlite3VdbeAddOp(v, OP_Close, newIdx, 0);
sqlite3VdbeAddOp(v, OP_Close, oldIdx, 0);
}
/*
** 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->trigStack && pParse->nested==0 ){
sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, "rows updated", P3_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqliteFree(apIdx);
sqliteFree(aXRef);
sqlite3SrcListDelete(pTabList);
sqlite3ExprListDelete(pChanges);
sqlite3ExprDelete(pWhere);
return;
}
/*
** This routine is call to handle SQL of the following forms:
**
** insert into TABLE (IDLIST) values(EXPRLIST)
** insert into TABLE (IDLIST) select
**
** The IDLIST following the table name is always optional. If omitted,
** then a list of all columns for the table is substituted. The IDLIST
** appears in the pColumn parameter. pColumn is NULL if IDLIST is omitted.
**
** The pList parameter holds EXPRLIST in the first form of the INSERT
** statement above, and pSelect is NULL. For the second form, pList is
** NULL and pSelect is a pointer to the select statement used to generate
** data for the insert.
**
** The code generated follows one of three templates. For a simple
** select with data coming from a VALUES clause, the code executes
** once straight down through. The template looks like this:
**
** open write cursor to <table> and its indices
** puts VALUES clause expressions onto the stack
** write the resulting record into <table>
** cleanup
**
** If the statement is of the form
**
** INSERT INTO <table> SELECT ...
**
** And the SELECT clause does not read from <table> at any time, then
** the generated code follows this template:
**
** goto B
** A: setup for the SELECT
** loop over the tables in the SELECT
** gosub C
** end loop
** cleanup after the SELECT
** goto D
** B: open write cursor to <table> and its indices
** goto A
** C: insert the select result into <table>
** return
** D: cleanup
**
** The third template is used if the insert statement takes its
** values from a SELECT but the data is being inserted into a table
** that is also read as part of the SELECT. In the third form,
** we have to use a intermediate table to store the results of
** the select. The template is like this:
**
** goto B
** A: setup for the SELECT
** loop over the tables in the SELECT
** gosub C
** end loop
** cleanup after the SELECT
** goto D
** C: insert the select result into the intermediate table
** return
** B: open a cursor to an intermediate table
** goto A
** D: open write cursor to <table> and its indices
** loop over the intermediate table
** transfer values form intermediate table into <table>
** end the loop
** cleanup
*/
void sqlite3Insert(
Parse *pParse, /* Parser context */
SrcList *pTabList, /* Name of table into which we are inserting */
ExprList *pList, /* List of values to be inserted */
Select *pSelect, /* A SELECT statement to use as the data source */
IdList *pColumn, /* Column names corresponding to IDLIST. */
int onError /* How to handle constraint errors */
){
Table *pTab; /* The table to insert into */
char *zTab; /* Name of the table into which we are inserting */
const char *zDb; /* Name of the database holding this table */
int i, j, idx; /* Loop counters */
Vdbe *v; /* Generate code into this virtual machine */
Index *pIdx; /* For looping over indices of the table */
int nColumn; /* Number of columns in the data */
int base = 0; /* VDBE Cursor number for pTab */
int iCont=0,iBreak=0; /* Beginning and end of the loop over srcTab */
sqlite3 *db; /* The main database structure */
int keyColumn = -1; /* Column that is the INTEGER PRIMARY KEY */
int endOfLoop; /* Label for the end of the insertion loop */
int useTempTable = 0; /* Store SELECT results in intermediate table */
int srcTab = 0; /* Data comes from this temporary cursor if >=0 */
int iSelectLoop = 0; /* Address of code that implements the SELECT */
int iCleanup = 0; /* Address of the cleanup code */
int iInsertBlock = 0; /* Address of the subroutine used to insert data */
int iCntMem = 0; /* Memory cell used for the row counter */
int newIdx = -1; /* Cursor for the NEW table */
Db *pDb; /* The database containing table being inserted into */
int counterMem = 0; /* Memory cell holding AUTOINCREMENT counter */
int iDb;
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to insert into a view */
int triggers_exist = 0; /* True if there are FOR EACH ROW triggers */
#endif
#ifndef SQLITE_OMIT_AUTOINCREMENT
int counterRowid = 0; /* Memory cell holding rowid of autoinc counter */
#endif
if( pParse->nErr || sqlite3MallocFailed() ){
goto insert_cleanup;
}
db = pParse->db;
/* Locate the table into which we will be inserting new information.
*/
assert( pTabList->nSrc==1 );
zTab = pTabList->a[0].zName;
if( zTab==0 ) goto insert_cleanup;
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ){
goto insert_cleanup;
}
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
pDb = &db->aDb[iDb];
zDb = pDb->zName;
if( sqlite3AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
goto insert_cleanup;
}
/* Figure out if we have any triggers and if the table being
** inserted into is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_INSERT, 0);
isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
/* Ensure that:
* (a) the table is not read-only,
* (b) that if it is a view then ON INSERT triggers exist
*/
if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
goto insert_cleanup;
}
assert( pTab!=0 );
/* If pTab is really a view, make sure it has been initialized.
*/
if( isView && sqlite3ViewGetColumnNames(pParse, pTab) ){
goto insert_cleanup;
}
/* Allocate a VDBE
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto insert_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, pSelect || triggers_exist, iDb);
/* if there are row triggers, allocate a temp table for new.* references. */
if( triggers_exist ){
newIdx = pParse->nTab++;
}
#ifndef SQLITE_OMIT_AUTOINCREMENT
/* If this is an AUTOINCREMENT table, look up the sequence number in the
** sqlite_sequence table and store it in memory cell counterMem. Also
** remember the rowid of the sqlite_sequence table entry in memory cell
** counterRowid.
*/
if( pTab->autoInc ){
int iCur = pParse->nTab;
int addr = sqlite3VdbeCurrentAddr(v);
counterRowid = pParse->nMem++;
counterMem = pParse->nMem++;
sqlite3OpenTable(pParse, iCur, iDb, pDb->pSchema->pSeqTab, OP_OpenRead);
sqlite3VdbeAddOp(v, OP_Rewind, iCur, addr+13);
sqlite3VdbeAddOp(v, OP_Column, iCur, 0);
sqlite3VdbeOp3(v, OP_String8, 0, 0, pTab->zName, 0);
sqlite3VdbeAddOp(v, OP_Ne, 0x100, addr+12);
sqlite3VdbeAddOp(v, OP_Rowid, iCur, 0);
sqlite3VdbeAddOp(v, OP_MemStore, counterRowid, 1);
sqlite3VdbeAddOp(v, OP_Column, iCur, 1);
sqlite3VdbeAddOp(v, OP_MemStore, counterMem, 1);
sqlite3VdbeAddOp(v, OP_Goto, 0, addr+13);
sqlite3VdbeAddOp(v, OP_Next, iCur, addr+4);
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}
#endif /* SQLITE_OMIT_AUTOINCREMENT */
/* Figure out how many columns of data are supplied. If the data
** is coming from a SELECT statement, then this step also generates
** all the code to implement the SELECT statement and invoke a subroutine
** to process each row of the result. (Template 2.) If the SELECT
** statement uses the the table that is being inserted into, then the
** subroutine is also coded here. That subroutine stores the SELECT
** results in a temporary table. (Template 3.)
*/
if( pSelect ){
/* Data is coming from a SELECT. Generate code to implement that SELECT
*/
int rc, iInitCode;
iInitCode = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
iSelectLoop = sqlite3VdbeCurrentAddr(v);
iInsertBlock = sqlite3VdbeMakeLabel(v);
/* Resolve the expressions in the SELECT statement and execute it. */
rc = sqlite3Select(pParse, pSelect, SRT_Subroutine, iInsertBlock,0,0,0,0);
if( rc || pParse->nErr || sqlite3MallocFailed() ){
goto insert_cleanup;
}
iCleanup = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp(v, OP_Goto, 0, iCleanup);
assert( pSelect->pEList );
nColumn = pSelect->pEList->nExpr;
/* Set useTempTable to TRUE if the result of the SELECT statement
** should be written into a temporary table. Set to FALSE if each
** row of the SELECT can be written directly into the result table.
**
** A temp table must be used if the table being updated is also one
** of the tables being read by the SELECT statement. Also use a
** temp table in the case of row triggers.
*/
if( triggers_exist || selectReadsTable(pSelect,pTab->pSchema,pTab->tnum) ){
useTempTable = 1;
}
if( useTempTable ){
/* Generate the subroutine that SELECT calls to process each row of
** the result. Store the result in a temporary table
*/
srcTab = pParse->nTab++;
sqlite3VdbeResolveLabel(v, iInsertBlock);
sqlite3VdbeAddOp(v, OP_MakeRecord, nColumn, 0);
sqlite3VdbeAddOp(v, OP_NewRowid, srcTab, 0);
sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
sqlite3VdbeAddOp(v, OP_Insert, srcTab, 0);
sqlite3VdbeAddOp(v, OP_Return, 0, 0);
/* The following code runs first because the GOTO at the very top
** of the program jumps to it. Create the temporary table, then jump
** back up and execute the SELECT code above.
*/
sqlite3VdbeJumpHere(v, iInitCode);
sqlite3VdbeAddOp(v, OP_OpenVirtual, srcTab, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, srcTab, nColumn);
sqlite3VdbeAddOp(v, OP_Goto, 0, iSelectLoop);
sqlite3VdbeResolveLabel(v, iCleanup);
}else{
sqlite3VdbeJumpHere(v, iInitCode);
}
}else{
/* This is the case if the data for the INSERT is coming from a VALUES
** clause
*/
NameContext sNC;
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
assert( pList!=0 );
srcTab = -1;
useTempTable = 0;
assert( pList );
nColumn = pList->nExpr;
for(i=0; i<nColumn; i++){
if( sqlite3ExprResolveNames(&sNC, pList->a[i].pExpr) ){
goto insert_cleanup;
}
}
}
/* Make sure the number of columns in the source data matches the number
** of columns to be inserted into the table.
*/
if( pColumn==0 && nColumn!=pTab->nCol ){
sqlite3ErrorMsg(pParse,
"table %S has %d columns but %d values were supplied",
pTabList, 0, pTab->nCol, nColumn);
goto insert_cleanup;
}
if( pColumn!=0 && nColumn!=pColumn->nId ){
sqlite3ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId);
goto insert_cleanup;
}
/* If the INSERT statement included an IDLIST term, then make sure
** all elements of the IDLIST really are columns of the table and
** remember the column indices.
**
** If the table has an INTEGER PRIMARY KEY column and that column
** is named in the IDLIST, then record in the keyColumn variable
** the index into IDLIST of the primary key column. keyColumn is
** the index of the primary key as it appears in IDLIST, not as
** is appears in the original table. (The index of the primary
** key in the original table is pTab->iPKey.)
*/
if( pColumn ){
for(i=0; i<pColumn->nId; i++){
pColumn->a[i].idx = -1;
}
for(i=0; i<pColumn->nId; i++){
for(j=0; j<pTab->nCol; j++){
if( sqlite3StrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){
pColumn->a[i].idx = j;
if( j==pTab->iPKey ){
keyColumn = i;
}
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pColumn->a[i].zName) ){
keyColumn = i;
}else{
sqlite3ErrorMsg(pParse, "table %S has no column named %s",
pTabList, 0, pColumn->a[i].zName);
pParse->nErr++;
goto insert_cleanup;
}
}
}
}
/* If there is no IDLIST term but the table has an integer primary
** key, the set the keyColumn variable to the primary key column index
** in the original table definition.
*/
if( pColumn==0 ){
keyColumn = pTab->iPKey;
}
/* Open the temp table for FOR EACH ROW triggers
*/
if( triggers_exist ){
sqlite3VdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, newIdx, pTab->nCol);
}
/* Initialize the count of rows to be inserted
*/
if( db->flags & SQLITE_CountRows ){
iCntMem = pParse->nMem++;
sqlite3VdbeAddOp(v, OP_MemInt, 0, iCntMem);
}
/* Open tables and indices if there are no row triggers */
if( !triggers_exist ){
base = pParse->nTab;
sqlite3OpenTableAndIndices(pParse, pTab, base, OP_OpenWrite);
}
/* If the data source is a temporary table, then we have to create
** a loop because there might be multiple rows of data. If the data
** source is a subroutine call from the SELECT statement, then we need
** to launch the SELECT statement processing.
*/
if( useTempTable ){
iBreak = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp(v, OP_Rewind, srcTab, iBreak);
iCont = sqlite3VdbeCurrentAddr(v);
}else if( pSelect ){
sqlite3VdbeAddOp(v, OP_Goto, 0, iSelectLoop);
sqlite3VdbeResolveLabel(v, iInsertBlock);
}
/* Run the BEFORE and INSTEAD OF triggers, if there are any
*/
endOfLoop = sqlite3VdbeMakeLabel(v);
if( triggers_exist & TRIGGER_BEFORE ){
/* build the NEW.* reference row. Note that if there is an INTEGER
** PRIMARY KEY into which a NULL is being inserted, that NULL will be
** translated into a unique ID for the row. But on a BEFORE trigger,
** we do not know what the unique ID will be (because the insert has
** not happened yet) so we substitute a rowid of -1
*/
if( keyColumn<0 ){
sqlite3VdbeAddOp(v, OP_Integer, -1, 0);
}else if( useTempTable ){
sqlite3VdbeAddOp(v, OP_Column, srcTab, keyColumn);
}else{
assert( pSelect==0 ); /* Otherwise useTempTable is true */
sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr);
sqlite3VdbeAddOp(v, OP_NotNull, -1, sqlite3VdbeCurrentAddr(v)+3);
sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
sqlite3VdbeAddOp(v, OP_Integer, -1, 0);
sqlite3VdbeAddOp(v, OP_MustBeInt, 0, 0);
}
/* Create the new column data
*/
for(i=0; i<pTab->nCol; i++){
if( pColumn==0 ){
j = i;
}else{
for(j=0; j<pColumn->nId; j++){
if( pColumn->a[j].idx==i ) break;
}
}
if( pColumn && j>=pColumn->nId ){
sqlite3ExprCode(pParse, pTab->aCol[i].pDflt);
}else if( useTempTable ){
sqlite3VdbeAddOp(v, OP_Column, srcTab, j);
}else{
assert( pSelect==0 ); /* Otherwise useTempTable is true */
sqlite3ExprCodeAndCache(pParse, pList->a[j].pExpr);
}
}
sqlite3VdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
/* If this is an INSERT on a view with an INSTEAD OF INSERT trigger,
** do not attempt any conversions before assembling the record.
** If this is a real table, attempt conversions as required by the
** table column affinities.
*/
if( !isView ){
sqlite3TableAffinityStr(v, pTab);
}
sqlite3VdbeAddOp(v, OP_Insert, newIdx, 0);
/* Fire BEFORE or INSTEAD OF triggers */
if( sqlite3CodeRowTrigger(pParse, TK_INSERT, 0, TRIGGER_BEFORE, pTab,
newIdx, -1, onError, endOfLoop) ){
goto insert_cleanup;
}
}
/* If any triggers exists, the opening of tables and indices is deferred
** until now.
*/
if( triggers_exist && !isView ){
base = pParse->nTab;
sqlite3OpenTableAndIndices(pParse, pTab, base, OP_OpenWrite);
}
/* Push the record number for the new entry onto the stack. The
** record number is a randomly generate integer created by NewRowid
** except when the table has an INTEGER PRIMARY KEY column, in which
** case the record number is the same as that column.
*/
if( !isView ){
if( keyColumn>=0 ){
if( useTempTable ){
sqlite3VdbeAddOp(v, OP_Column, srcTab, keyColumn);
}else if( pSelect ){
sqlite3VdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
}else{
sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr);
}
/* If the PRIMARY KEY expression is NULL, then use OP_NewRowid
** to generate a unique primary key value.
*/
sqlite3VdbeAddOp(v, OP_NotNull, -1, sqlite3VdbeCurrentAddr(v)+3);
sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
sqlite3VdbeAddOp(v, OP_NewRowid, base, counterMem);
sqlite3VdbeAddOp(v, OP_MustBeInt, 0, 0);
}else{
sqlite3VdbeAddOp(v, OP_NewRowid, base, counterMem);
}
#ifndef SQLITE_OMIT_AUTOINCREMENT
if( pTab->autoInc ){
sqlite3VdbeAddOp(v, OP_MemMax, counterMem, 0);
}
#endif /* SQLITE_OMIT_AUTOINCREMENT */
/* Push onto the stack, data for all columns of the new entry, beginning
** with the first column.
*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
/* The value of the INTEGER PRIMARY KEY column is always a NULL.
** Whenever this column is read, the record number will be substituted
** in its place. So will fill this column with a NULL to avoid
** taking up data space with information that will never be used. */
sqlite3VdbeAddOp(v, OP_Null, 0, 0);
continue;
}
if( pColumn==0 ){
j = i;
}else{
for(j=0; j<pColumn->nId; j++){
if( pColumn->a[j].idx==i ) break;
}
}
if( pColumn && j>=pColumn->nId ){
sqlite3ExprCode(pParse, pTab->aCol[i].pDflt);
}else if( useTempTable ){
sqlite3VdbeAddOp(v, OP_Column, srcTab, j);
}else if( pSelect ){
sqlite3VdbeAddOp(v, OP_Dup, i+nColumn-j, 1);
}else{
sqlite3ExprCode(pParse, pList->a[j].pExpr);
}
}
/* Generate code to check constraints and generate index keys and
** do the insertion.
*/
sqlite3GenerateConstraintChecks(pParse, pTab, base, 0, keyColumn>=0,
0, onError, endOfLoop);
sqlite3CompleteInsertion(pParse, pTab, base, 0,0,0,
(triggers_exist & TRIGGER_AFTER)!=0 ? newIdx : -1);
}
/* Update the count of rows that are inserted
*/
if( (db->flags & SQLITE_CountRows)!=0 ){
sqlite3VdbeAddOp(v, OP_MemIncr, 1, iCntMem);
}
if( triggers_exist ){
/* Close all tables opened */
if( !isView ){
sqlite3VdbeAddOp(v, OP_Close, base, 0);
for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
sqlite3VdbeAddOp(v, OP_Close, idx+base, 0);
}
}
/* Code AFTER triggers */
if( sqlite3CodeRowTrigger(pParse, TK_INSERT, 0, TRIGGER_AFTER, pTab,
newIdx, -1, onError, endOfLoop) ){
goto insert_cleanup;
}
}
/* The bottom of the loop, if the data source is a SELECT statement
*/
sqlite3VdbeResolveLabel(v, endOfLoop);
if( useTempTable ){
sqlite3VdbeAddOp(v, OP_Next, srcTab, iCont);
sqlite3VdbeResolveLabel(v, iBreak);
sqlite3VdbeAddOp(v, OP_Close, srcTab, 0);
}else if( pSelect ){
sqlite3VdbeAddOp(v, OP_Pop, nColumn, 0);
sqlite3VdbeAddOp(v, OP_Return, 0, 0);
sqlite3VdbeResolveLabel(v, iCleanup);
}
if( !triggers_exist ){
/* Close all tables opened */
sqlite3VdbeAddOp(v, OP_Close, base, 0);
for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
sqlite3VdbeAddOp(v, OP_Close, idx+base, 0);
}
}
#ifndef SQLITE_OMIT_AUTOINCREMENT
/* Update the sqlite_sequence table by storing the content of the
** counter value in memory counterMem back into the sqlite_sequence
** table.
*/
if( pTab->autoInc ){
int iCur = pParse->nTab;
int addr = sqlite3VdbeCurrentAddr(v);
sqlite3OpenTable(pParse, iCur, iDb, pDb->pSchema->pSeqTab, OP_OpenWrite);
sqlite3VdbeAddOp(v, OP_MemLoad, counterRowid, 0);
sqlite3VdbeAddOp(v, OP_NotNull, -1, addr+7);
sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
sqlite3VdbeAddOp(v, OP_NewRowid, iCur, 0);
sqlite3VdbeOp3(v, OP_String8, 0, 0, pTab->zName, 0);
sqlite3VdbeAddOp(v, OP_MemLoad, counterMem, 0);
sqlite3VdbeAddOp(v, OP_MakeRecord, 2, 0);
sqlite3VdbeAddOp(v, OP_Insert, iCur, 0);
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}
#endif
/*
** Return the number of rows inserted. 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==0 && !pParse->trigStack ){
sqlite3VdbeAddOp(v, OP_MemLoad, iCntMem, 0);
sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows inserted", P3_STATIC);
}
insert_cleanup:
sqlite3SrcListDelete(pTabList);
sqlite3ExprListDelete(pList);
sqlite3SelectDelete(pSelect);
sqlite3IdListDelete(pColumn);
}
/*
** 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 = 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
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( IsPrimaryKeyIndex(pIdx) && 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.
**
** FIXME: Be smarter about omitting indexes that use expressions.
*/
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++){
i16 iIdxCol = pIdx->aiColumn[i];
if( iIdxCol<0 || aXRef[iIdxCol]>=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);
/* 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, iDataCur);
}
#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
/* 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++){
assert( pPk->aiColumn[i]>=0 );
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(db, 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, 0, iBaseCur, aToOpen,
0, 0);
}
/* Top of the update loop */
if( okOnePass ){
if( aToOpen[iDataCur-iBaseCur] && !isView ){
assert( pPk );
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelBreak, regKey, nKey);
VdbeCoverageNeverTaken(v);
}
labelContinue = labelBreak;
sqlite3VdbeAddOp2(v, OP_IsNull, pPk ? regKey : regOldRowid, labelBreak);
VdbeCoverageIf(v, pPk==0);
VdbeCoverageIf(v, pPk!=0);
}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 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 );
sqlite3ExprCodeGetColumnToReg(pParse, pTab, i, iDataCur, 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 addr1 = 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 ){
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 record number, delete the old record. */
if( hasFK || chngKey || pPk!=0 ){
sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, 0);
}
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, 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{
sqlite3VdbeGoto(v, 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;
}
void sqlite3Update(
Parse *pParse,
SrcList *pTabList,
ExprList *pChanges,
Expr *pWhere,
int onError
){
int i, j;
Table *pTab;
int addr = 0;
WhereInfo *pWInfo;
Vdbe *v;
Index *pIdx;
int nIdx;
int iCur;
sqlite3 *db;
int *aRegIdx = 0;
int *aXRef = 0;
int chngRowid;
Expr *pRowidExpr = 0;
int openAll = 0;
AuthContext sContext;
NameContext sNC;
int iDb;
int okOnePass;
int hasFK;
#ifndef SQLITE_OMIT_TRIGGER
int isView;
Trigger *pTrigger;
int tmask;
#endif
int newmask;
int regRowCount = 0;
int regOldRowid;
int regNewRowid;
int regNew;
int regOld = 0;
int regRowSet = 0;
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto update_cleanup;
}
assert( pTabList->nSrc==1 );
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
#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;
}
aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto update_cleanup;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
pTabList->a[0].iCursor = iCur = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
chngRowid = 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;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pChanges->a[i].zName) ){
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,
pTab->aCol[j].zName, db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
hasFK = sqlite3FkRequired(pParse, pTab, aXRef, chngRowid);
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
if( nIdx>0 ){
aRegIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx );
if( aRegIdx==0 ) goto update_cleanup;
}
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngRowid ){
reg = ++pParse->nMem;
}else{
reg = 0;
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ){
reg = ++pParse->nMem;
break;
}
}
}
aRegIdx[j] = reg;
}
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
pWhere);
pWhere = 0;
pTabList = 0;
goto update_cleanup;
}
#endif
regOldRowid = regNewRowid = ++pParse->nMem;
if( pTrigger || hasFK ){
regOld = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
}
if( chngRowid || pTrigger || hasFK ){
regNewRowid = ++pParse->nMem;
}
regNew = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
}
#endif
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto update_cleanup;
}
sqlite3VdbeAddOp2(v, OP_Null, 0, regOldRowid);
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,0, WHERE_ONEPASS_DESIRED);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = pWInfo->okOnePass;
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regOldRowid);
if( !okOnePass ){
regRowSet = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
}
sqlite3WhereEnd(pWInfo);
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab ){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
if( !isView ){
if( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
(char*)pKey, P4_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
}
if( okOnePass ){
int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
addr = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, a1);
}else{
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet, 0, regOldRowid);
}
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
assert( chngRowid || pTrigger || hasFK || regOldRowid==regNewRowid );
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
}
if( 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( aXRef[i]<0 || oldmask==0xffffffff || (i<32 && (oldmask & (1<<i))) ){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, i, regOld+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regOld+i);
}
}
if( chngRowid==0 ){
sqlite3VdbeAddOp2(v, OP_Copy, regOldRowid, regNewRowid);
}
}
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&(1<<i)) ){
testcase( i==31 );
testcase( i==32 );
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
sqlite3ColumnDefault(v, pTab, i, regNew+i);
}
}
}
if( tmask&TRIGGER_BEFORE ){
sqlite3VdbeAddOp2(v, OP_Affinity, regNew, pTab->nCol);
sqlite3TableAffinityStr(v, pTab);
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_BEFORE, pTab, regOldRowid, onError, addr);
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]<0 && i!=pTab->iPKey ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
sqlite3ColumnDefault(v, pTab, i, regNew+i);
}
}
}
if( !isView ){
int j1;
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
aRegIdx, (chngRowid?regOldRowid:0), 1, onError, addr, 0);
if( hasFK ){
sqlite3FkCheck(pParse, pTab, regOldRowid, 0);
}
j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
if( hasFK || chngRowid ){
sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
}
sqlite3VdbeJumpHere(v, j1);
if( hasFK ){
sqlite3FkCheck(pParse, pTab, 0, regNewRowid);
}
sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid, aRegIdx, 1, 0, 0);
if( hasFK ){
sqlite3FkActions(pParse, pTab, pChanges, regOldRowid);
}
}
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab){
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_AFTER, pTab, regOldRowid, onError, addr);
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeJumpHere(v, addr);
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
sqlite3VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
}
}
sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
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, aRegIdx);
sqlite3DbFree(db, aXRef);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
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 addr = 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 */
int nIdx; /* Number of indices that need updating */
int iCur; /* VDBE Cursor number of pTab */
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. */
int chngRowid; /* True if the record number is being changed */
Expr *pRowidExpr = 0; /* Expression defining the new record number */
int openAll = 0; /* True if all indices need to be opened */
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 */
#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 */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid; /* The old rowid */
int regNewRowid; /* The new rowid */
int regNew;
int regOld = 0;
int regRowSet = 0; /* Rowset of rows to be updated */
int regRec; /* Register used for new table record to insert */
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
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, tmask) ){
goto update_cleanup;
}
aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto update_cleanup;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* 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 = iCur = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* 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 = 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;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pChanges->a[i].zName) ){
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,
pTab->aCol[j].zName, db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
hasFK = sqlite3FkRequired(pParse, pTab, aXRef, chngRowid);
/* Allocate memory for the array aRegIdx[]. There is one entry in the
** array for each index associated with table being updated. Fill in
** the value with a register number for indices that are to be used
** and with zero for unused indices.
*/
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
if( nIdx>0 ){
aRegIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx );
if( aRegIdx==0 ) goto update_cleanup;
}
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngRowid ){
reg = ++pParse->nMem;
}else{
reg = 0;
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ){
reg = ++pParse->nMem;
break;
}
}
}
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);
pWhere = 0;
pTabList = 0;
goto update_cleanup;
}
#endif
/* Allocate required registers. */
regOldRowid = regNewRowid = ++pParse->nMem;
if( pTrigger || hasFK ){
regOld = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
}
if( chngRowid || pTrigger || hasFK ){
regNewRowid = ++pParse->nMem;
}
regNew = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
regRec = ++pParse->nMem;
/* 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, iCur);
}
#endif
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto update_cleanup;
}
/* Begin the database scan
*/
sqlite3VdbeAddOp2(v, OP_Null, 0, regOldRowid);
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,0, WHERE_ONEPASS_DESIRED);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = pWInfo->okOnePass;
/* Remember the rowid of every item to be updated.
*/
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regOldRowid);
if( !okOnePass ){
regRowSet = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
}
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
/* Initialize the count of updated rows
*/
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab ){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
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( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
(char*)pKey, P4_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
}
/* Top of the update loop */
if( okOnePass ){
int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
addr = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, a1);
}else{
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet, 0, regOldRowid);
}
/* Make cursor iCur point to the record that is being updated. If
** this record does not exist for some reason (deleted by a trigger,
** for example, then jump to the next iteration of the RowSet loop. */
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* 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( chngRowid || pTrigger || hasFK || regOldRowid==regNewRowid );
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
}
/* If there are triggers on this table, populate an array of registers
** with the required old.* column data. */
if( 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( aXRef[i]<0 || oldmask==0xffffffff || (oldmask & (1<<i)) ){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, i, regOld+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regOld+i);
}
}
if( chngRowid==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
);
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&(1<<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 );
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
sqlite3ColumnDefault(v, pTab, i, regNew+i);
}
}
}
/* Fire any BEFORE UPDATE triggers. This happens before constraints are
** verified. One could argue that this is wrong.
*/
if( tmask&TRIGGER_BEFORE ){
sqlite3VdbeAddOp2(v, OP_Affinity, regNew, pTab->nCol);
sqlite3TableAffinityStr(v, pTab);
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_BEFORE, pTab, regOldRowid, onError, addr);
/* 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 behaviour - what happens when the row being updated
** is deleted or renamed by a BEFORE trigger - is left undefined in the
** documentation.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* 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 ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
sqlite3ColumnDefault(v, pTab, i, regNew+i);
}
}
}
if( !isView ){
int j1; /* Address of jump instruction */
/* Do constraint checks. */
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
aRegIdx, (chngRowid?regOldRowid:0), 1, onError, addr, 0);
/* Do FK constraint checks. */
if( hasFK ){
sqlite3FkCheck(pParse, pTab, regOldRowid, 0);
}
/* Delete the index entries associated with the current record. */
j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
/* If changing the record number, delete the old record. */
if( hasFK || chngRowid ){
sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
}
sqlite3VdbeJumpHere(v, j1);
if( hasFK ){
sqlite3FkCheck(pParse, pTab, 0, regNewRowid);
}
/* Insert the new index entries and the new record. */
sqlite3CompleteInsertion(pParse, pTab, iCur, 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);
}
}
/* 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, addr);
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeJumpHere(v, addr);
/* Close all tables */
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
sqlite3VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
}
}
sqlite3VdbeAddOp2(v, OP_Close, iCur, 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, aRegIdx);
sqlite3DbFree(db, aXRef);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
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 addr = 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 */
int nIdx; /* Number of indices that need updating */
int iCur; /* VDBE Cursor number of pTab */
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. */
int chngRowid; /* True if the record number is being changed */
Expr *pRowidExpr = 0; /* Expression defining the new record number */
int openAll = 0; /* True if all indices need to be opened */
AuthContext sContext; /* The authorization context */
NameContext sNC; /* The name-context to resolve expressions in */
int iDb; /* Database containing the table being updated */
int j1; /* Addresses of jump instructions */
int okOnePass; /* True for one-pass algorithm without the FIFO */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* Trying to update a view */
int triggers_exist = 0; /* True if any row triggers exist */
#endif
int iBeginAfterTrigger = 0; /* Address of after trigger program */
int iEndAfterTrigger = 0; /* Exit of after trigger program */
int iBeginBeforeTrigger = 0; /* Address of before trigger program */
int iEndBeforeTrigger = 0; /* Exit of before trigger program */
u32 old_col_mask = 0; /* Mask of OLD.* columns in use */
u32 new_col_mask = 0; /* Mask of NEW.* columns in use */
int newIdx = -1; /* index of trigger "new" temp table */
int oldIdx = -1; /* index of trigger "old" temp table */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid; /* The old rowid */
int regNewRowid; /* The new rowid */
int regData; /* New data for the row */
int regRowSet = 0; /* Rowset of rows to be updated */
sContext.pParse = 0;
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
triggers_exist = sqlite3TriggersExist(pTab, TK_UPDATE, pChanges);
isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
goto update_cleanup;
}
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto update_cleanup;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* If there are FOR EACH ROW triggers, allocate cursors for the
** special OLD and NEW tables
*/
if( triggers_exist ){
newIdx = pParse->nTab++;
oldIdx = pParse->nTab++;
}
/* 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 = iCur = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* 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 = 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;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pChanges->a[i].zName) ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
pTab->aCol[j].zName, db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
/* Allocate memory for the array aRegIdx[]. There is one entry in the
** array for each index associated with table being updated. Fill in
** the value with a register number for indices that are to be used
** and with zero for unused indices.
*/
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
if( nIdx>0 ){
aRegIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx );
if( aRegIdx==0 ) goto update_cleanup;
}
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngRowid ){
reg = ++pParse->nMem;
}else{
reg = 0;
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ){
reg = ++pParse->nMem;
break;
}
}
}
aRegIdx[j] = reg;
}
/* Allocate a block of register used to store the change record
** sent to sqlite3GenerateConstraintChecks(). There are either
** one or two registers for holding the rowid. One rowid register
** is used if chngRowid is false and two are used if chngRowid is
** true. Following these are pTab->nCol register holding column
** data.
*/
regOldRowid = regNewRowid = pParse->nMem + 1;
pParse->nMem += pTab->nCol + 1;
if( chngRowid ){
regNewRowid++;
pParse->nMem++;
}
regData = regNewRowid+1;
/* 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);
pWhere = 0;
pTabList = 0;
goto update_cleanup;
}
#endif
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Generate the code for triggers.
*/
if( triggers_exist ){
int iGoto;
/* Create pseudo-tables for NEW and OLD
*/
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
sqlite3VdbeAddOp2(v, OP_OpenPseudo, oldIdx, 0);
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
sqlite3VdbeAddOp2(v, OP_OpenPseudo, newIdx, 0);
iGoto = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
addr = sqlite3VdbeMakeLabel(v);
iBeginBeforeTrigger = sqlite3VdbeCurrentAddr(v);
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_BEFORE, pTab,
newIdx, oldIdx, onError, addr, &old_col_mask, &new_col_mask) ){
goto update_cleanup;
}
iEndBeforeTrigger = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
iBeginAfterTrigger = sqlite3VdbeCurrentAddr(v);
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_AFTER, pTab,
newIdx, oldIdx, onError, addr, &old_col_mask, &new_col_mask) ){
goto update_cleanup;
}
iEndAfterTrigger = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
sqlite3VdbeJumpHere(v, iGoto);
}
/* 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, iCur);
}
#endif
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto update_cleanup;
}
/* Begin the database scan
*/
sqlite3VdbeAddOp2(v, OP_Null, 0, regOldRowid);
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0,
WHERE_ONEPASS_DESIRED, 0);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = pWInfo->okOnePass;
/* Remember the rowid of every item to be updated.
*/
sqlite3VdbeAddOp2(v, IsVirtual(pTab)?OP_VRowid:OP_Rowid, iCur, regOldRowid);
if( !okOnePass ){
regRowSet = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
}
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
/* Initialize the count of updated rows
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
if( !isView && !IsVirtual(pTab) ){
/*
** 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( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
(char*)pKey, P4_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
}
/* Jump back to this point if a trigger encounters an IGNORE constraint. */
if( triggers_exist ){
sqlite3VdbeResolveLabel(v, addr);
}
/* Top of the update loop */
if( okOnePass ){
int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
addr = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, a1);
}else{
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet, 0, regOldRowid);
}
if( triggers_exist ){
int regRowid;
int regRow;
int regCols;
/* Make cursor iCur point to the record that is being updated.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* Generate the OLD table
*/
regRowid = sqlite3GetTempReg(pParse);
regRow = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regRowid);
if( !old_col_mask ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regRow);
}else{
sqlite3VdbeAddOp2(v, OP_RowData, iCur, regRow);
}
sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, regRow, regRowid);
/* Generate the NEW table
*/
if( chngRowid ){
sqlite3ExprCodeAndCache(pParse, pRowidExpr, regRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid);
}else{
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regRowid);
}
regCols = sqlite3GetTempRange(pParse, pTab->nCol);
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regCols+i);
continue;
}
j = aXRef[i];
if( new_col_mask&((u32)1<<i) || new_col_mask==0xffffffff ){
if( j<0 ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regCols+i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCodeAndCache(pParse, pChanges->a[j].pExpr, regCols+i);
}
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regCols+i);
}
}
sqlite3VdbeAddOp3(v, OP_MakeRecord, regCols, pTab->nCol, regRow);
if( !isView ){
sqlite3TableAffinityStr(v, pTab);
sqlite3ExprCacheAffinityChange(pParse, regCols, pTab->nCol);
}
sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol);
/* if( pParse->nErr ) goto update_cleanup; */
sqlite3VdbeAddOp3(v, OP_Insert, newIdx, regRow, regRowid);
sqlite3ReleaseTempReg(pParse, regRowid);
sqlite3ReleaseTempReg(pParse, regRow);
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
}
if( !isView && !IsVirtual(pTab) ){
/* Loop over every record that needs updating. We have to load
** the old data for each record to be updated because some columns
** might not change and we will need to copy the old value.
** Also, the old data is needed to delete the old index entries.
** So make the cursor point at the old record.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* If the record number will change, push the record number as it
** will be after the update. (The old record number is currently
** on top of the stack.)
*/
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
}
/* Compute new data for this record.
*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regData+i);
continue;
}
j = aXRef[i];
if( j<0 ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regData+i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regData+i);
}
}
/* Do constraint checks
*/
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
aRegIdx, chngRowid, 1,
onError, addr);
/* Delete the old indices for the current record.
*/
j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
/* If changing the record number, delete the old record.
*/
if( chngRowid ){
sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
}
sqlite3VdbeJumpHere(v, j1);
/* Create the new index entries and the new record.
*/
sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid,
aRegIdx, 1, -1, 0);
}
/* Increment the row counter
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack){
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
/* If there are triggers, close all the cursors after each iteration
** through the loop. The fire the after triggers.
*/
if( triggers_exist ){
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginAfterTrigger);
sqlite3VdbeJumpHere(v, iEndAfterTrigger);
}
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeJumpHere(v, addr);
/* Close all tables */
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
sqlite3VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
}
}
sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
if( triggers_exist ){
sqlite3VdbeAddOp2(v, OP_Close, newIdx, 0);
sqlite3VdbeAddOp2(v, OP_Close, oldIdx, 0);
}
/*
** 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->trigStack && pParse->nested==0 ){
sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3DbFree(db, aRegIdx);
sqlite3DbFree(db, aXRef);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
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 */
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;
}