/*
** 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 sqliteInsert(
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; /* VDBE Cursor number for pTab */
int iCont, iBreak; /* Beginning and end of the loop over srcTab */
sqlite *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; /* Store SELECT results in intermediate table */
int srcTab; /* Data comes from this temporary cursor if >=0 */
int iSelectLoop; /* Address of code that implements the SELECT */
int iCleanup; /* Address of the cleanup code */
int iInsertBlock; /* Address of the subroutine used to insert data */
int iCntMem; /* Memory cell used for the row counter */
int isView; /* True if attempting to insert into a view */
int row_triggers_exist = 0; /* True if there are FOR EACH ROW triggers */
int before_triggers; /* True if there are BEFORE triggers */
int after_triggers; /* True if there are AFTER triggers */
int newIdx = -1; /* Cursor for the NEW table */
if( pParse->nErr || sqlite_malloc_failed ) 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 = sqliteSrcListLookup(pParse, pTabList);
if( pTab==0 ){
goto insert_cleanup;
}
assert( pTab->iDb<db->nDb );
zDb = db->aDb[pTab->iDb].zName;
if( sqliteAuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
goto insert_cleanup;
}
/* Ensure that:
* (a) the table is not read-only,
* (b) that if it is a view then ON INSERT triggers exist
*/
before_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, TK_INSERT,
TK_BEFORE, TK_ROW, 0);
after_triggers = sqliteTriggersExist(pParse, pTab->pTrigger, TK_INSERT,
TK_AFTER, TK_ROW, 0);
row_triggers_exist = before_triggers || after_triggers;
isView = pTab->pSelect!=0;
if( sqliteIsReadOnly(pParse, pTab, before_triggers) ){
goto insert_cleanup;
}
if( pTab==0 ) goto insert_cleanup;
/* If pTab is really a view, make sure it has been initialized.
*/
if( isView && sqliteViewGetColumnNames(pParse, pTab) ){
goto insert_cleanup;
}
/* Allocate a VDBE
*/
v = sqliteGetVdbe(pParse);
if( v==0 ) goto insert_cleanup;
sqliteBeginWriteOperation(pParse, pSelect || row_triggers_exist, pTab->iDb);
/* if there are row triggers, allocate a temp table for new.* references. */
if( row_triggers_exist ){
newIdx = pParse->nTab++;
}
/* 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 = sqliteVdbeAddOp(v, OP_Goto, 0, 0);
iSelectLoop = sqliteVdbeCurrentAddr(v);
iInsertBlock = sqliteVdbeMakeLabel(v);
rc = sqliteSelect(pParse, pSelect, SRT_Subroutine, iInsertBlock, 0,0,0);
if( rc || pParse->nErr || sqlite_malloc_failed ) goto insert_cleanup;
iCleanup = sqliteVdbeMakeLabel(v);
sqliteVdbeAddOp(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( row_triggers_exist ){
useTempTable = 1;
}else{
int addr = sqliteVdbeFindOp(v, OP_OpenRead, pTab->tnum);
useTempTable = 0;
if( addr>0 ){
VdbeOp *pOp = sqliteVdbeGetOp(v, addr-2);
if( pOp->opcode==OP_Integer && pOp->p1==pTab->iDb ){
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++;
sqliteVdbeResolveLabel(v, iInsertBlock);
sqliteVdbeAddOp(v, OP_MakeRecord, nColumn, 0);
sqliteVdbeAddOp(v, OP_NewRecno, srcTab, 0);
sqliteVdbeAddOp(v, OP_Pull, 1, 0);
sqliteVdbeAddOp(v, OP_PutIntKey, srcTab, 0);
sqliteVdbeAddOp(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.
*/
sqliteVdbeChangeP2(v, iInitCode, sqliteVdbeCurrentAddr(v));
sqliteVdbeAddOp(v, OP_OpenTemp, srcTab, 0);
sqliteVdbeAddOp(v, OP_Goto, 0, iSelectLoop);
sqliteVdbeResolveLabel(v, iCleanup);
}else{
sqliteVdbeChangeP2(v, iInitCode, sqliteVdbeCurrentAddr(v));
}
}else{
/* This is the case if the data for the INSERT is coming from a VALUES
** clause
*/
SrcList dummy;
assert( pList!=0 );
srcTab = -1;
useTempTable = 0;
assert( pList );
nColumn = pList->nExpr;
dummy.nSrc = 0;
for(i=0; i<nColumn; i++){
if( sqliteExprResolveIds(pParse, &dummy, 0, pList->a[i].pExpr) ){
goto insert_cleanup;
}
if( sqliteExprCheck(pParse, pList->a[i].pExpr, 0, 0) ){
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 ){
sqliteErrorMsg(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 ){
sqliteErrorMsg(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( sqliteStrICmp(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( sqliteIsRowid(pColumn->a[i].zName) ){
keyColumn = i;
}else{
sqliteErrorMsg(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( row_triggers_exist ){
sqliteVdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
}
/* Initialize the count of rows to be inserted
*/
if( db->flags & SQLITE_CountRows ){
iCntMem = pParse->nMem++;
sqliteVdbeAddOp(v, OP_Integer, 0, 0);
sqliteVdbeAddOp(v, OP_MemStore, iCntMem, 1);
}
/* Open tables and indices if there are no row triggers */
if( !row_triggers_exist ){
base = pParse->nTab;
idx = sqliteOpenTableAndIndices(pParse, pTab, base);
pParse->nTab += idx;
}
/* 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 = sqliteVdbeMakeLabel(v);
sqliteVdbeAddOp(v, OP_Rewind, srcTab, iBreak);
iCont = sqliteVdbeCurrentAddr(v);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Goto, 0, iSelectLoop);
sqliteVdbeResolveLabel(v, iInsertBlock);
}
/* Run the BEFORE and INSTEAD OF triggers, if there are any
*/
endOfLoop = sqliteVdbeMakeLabel(v);
if( before_triggers ){
/* 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 ){
sqliteVdbeAddOp(v, OP_Integer, -1, 0);
}else if( useTempTable ){
sqliteVdbeAddOp(v, OP_Column, srcTab, keyColumn);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
}else{
sqliteExprCode(pParse, pList->a[keyColumn].pExpr);
sqliteVdbeAddOp(v, OP_NotNull, -1, sqliteVdbeCurrentAddr(v)+3);
sqliteVdbeAddOp(v, OP_Pop, 1, 0);
sqliteVdbeAddOp(v, OP_Integer, -1, 0);
sqliteVdbeAddOp(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 ){
sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
}else if( useTempTable ){
sqliteVdbeAddOp(v, OP_Column, srcTab, j);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Dup, nColumn-j-1, 1);
}else{
sqliteExprCode(pParse, pList->a[j].pExpr);
}
}
sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
sqliteVdbeAddOp(v, OP_PutIntKey, newIdx, 0);
/* Fire BEFORE or INSTEAD OF triggers */
if( sqliteCodeRowTrigger(pParse, TK_INSERT, 0, TK_BEFORE, pTab,
newIdx, -1, onError, endOfLoop) ){
goto insert_cleanup;
}
}
/* If any triggers exists, the opening of tables and indices is deferred
** until now.
*/
if( row_triggers_exist && !isView ){
base = pParse->nTab;
idx = sqliteOpenTableAndIndices(pParse, pTab, base);
pParse->nTab += idx;
}
/* Push the record number for the new entry onto the stack. The
** record number is a randomly generate integer created by NewRecno
** 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 ){
sqliteVdbeAddOp(v, OP_Column, srcTab, keyColumn);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Dup, nColumn - keyColumn - 1, 1);
}else{
sqliteExprCode(pParse, pList->a[keyColumn].pExpr);
}
/* If the PRIMARY KEY expression is NULL, then use OP_NewRecno
** to generate a unique primary key value.
*/
sqliteVdbeAddOp(v, OP_NotNull, -1, sqliteVdbeCurrentAddr(v)+3);
sqliteVdbeAddOp(v, OP_Pop, 1, 0);
sqliteVdbeAddOp(v, OP_NewRecno, base, 0);
sqliteVdbeAddOp(v, OP_MustBeInt, 0, 0);
}else{
sqliteVdbeAddOp(v, OP_NewRecno, base, 0);
}
/* 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. */
sqliteVdbeAddOp(v, OP_String, 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 ){
sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
}else if( useTempTable ){
sqliteVdbeAddOp(v, OP_Column, srcTab, j);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Dup, i+nColumn-j, 1);
}else{
sqliteExprCode(pParse, pList->a[j].pExpr);
}
}
/* Generate code to check constraints and generate index keys and
** do the insertion.
*/
sqliteGenerateConstraintChecks(pParse, pTab, base, 0, keyColumn>=0,
0, onError, endOfLoop);
sqliteCompleteInsertion(pParse, pTab, base, 0,0,0,
after_triggers ? newIdx : -1);
}
/* Update the count of rows that are inserted
*/
if( (db->flags & SQLITE_CountRows)!=0 ){
sqliteVdbeAddOp(v, OP_MemIncr, iCntMem, 0);
}
if( row_triggers_exist ){
/* Close all tables opened */
if( !isView ){
sqliteVdbeAddOp(v, OP_Close, base, 0);
for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
sqliteVdbeAddOp(v, OP_Close, idx+base, 0);
}
}
/* Code AFTER triggers */
if( sqliteCodeRowTrigger(pParse, TK_INSERT, 0, TK_AFTER, pTab, newIdx, -1,
onError, endOfLoop) ){
goto insert_cleanup;
}
}
/* The bottom of the loop, if the data source is a SELECT statement
*/
sqliteVdbeResolveLabel(v, endOfLoop);
if( useTempTable ){
sqliteVdbeAddOp(v, OP_Next, srcTab, iCont);
sqliteVdbeResolveLabel(v, iBreak);
sqliteVdbeAddOp(v, OP_Close, srcTab, 0);
}else if( pSelect ){
sqliteVdbeAddOp(v, OP_Pop, nColumn, 0);
sqliteVdbeAddOp(v, OP_Return, 0, 0);
sqliteVdbeResolveLabel(v, iCleanup);
}
if( !row_triggers_exist ){
/* Close all tables opened */
sqliteVdbeAddOp(v, OP_Close, base, 0);
for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
sqliteVdbeAddOp(v, OP_Close, idx+base, 0);
}
}
sqliteVdbeAddOp(v, OP_SetCounts, 0, 0);
sqliteEndWriteOperation(pParse);
/*
** Return the number of rows inserted.
*/
if( db->flags & SQLITE_CountRows ){
sqliteVdbeOp3(v, OP_ColumnName, 0, 1, "rows inserted", P3_STATIC);
sqliteVdbeAddOp(v, OP_MemLoad, iCntMem, 0);
sqliteVdbeAddOp(v, OP_Callback, 1, 0);
}
insert_cleanup:
sqliteSrcListDelete(pTabList);
if( pList ) sqliteExprListDelete(pList);
if( pSelect ) sqliteSelectDelete(pSelect);
sqliteIdListDelete(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 sqliteUpdate(
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; /* 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 */
sqlite *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; /* Expression defining the new record number */
int openAll; /* True if all indices need to be opened */
int isView; /* Trying to update a view */
AuthContext sContext; /* The authorization context */
int before_triggers; /* True if there are any BEFORE triggers */
int after_triggers; /* True if there are any AFTER triggers */
int row_triggers_exist = 0; /* True if any row triggers exist */
int newIdx = -1; /* index of trigger "new" temp table */
int oldIdx = -1; /* index of trigger "old" temp table */
sContext.pParse = 0;
if( pParse->nErr || sqlite_malloc_failed ) goto update_cleanup;
db = pParse->db;
assert( pTabList->nSrc==1 );
/* Locate the table which we want to update.
*/
pTab = sqliteSrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
before_triggers = sqliteTriggersExist(pParse, pTab->pTrigger,
TK_UPDATE, TK_BEFORE, TK_ROW, pChanges);
after_triggers = sqliteTriggersExist(pParse, pTab->pTrigger,
TK_UPDATE, TK_AFTER, TK_ROW, pChanges);
row_triggers_exist = before_triggers || after_triggers;
isView = pTab->pSelect!=0;
if( sqliteIsReadOnly(pParse, pTab, before_triggers) ){
goto update_cleanup;
}
if( isView ){
if( sqliteViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
}
aXRef = sqliteMalloc( 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( row_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++;
}
/* 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( sqliteExprResolveIds(pParse, pTabList, 0, pChanges->a[i].pExpr) ){
goto update_cleanup;
}
if( sqliteExprCheck(pParse, pChanges->a[i].pExpr, 0, 0) ){
goto update_cleanup;
}
for(j=0; j<pTab->nCol; j++){
if( sqliteStrICmp(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( sqliteIsRowid(pChanges->a[i].zName) ){
chngRecno = 1;
pRecnoExpr = pChanges->a[i].pExpr;
}else{
sqliteErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqliteAuthCheck(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 = sqliteMalloc( 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 ){
apIdx[nIdx++] = pIdx;
aIdxUsed[j] = 1;
}else{
aIdxUsed[j] = 0;
}
}
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( pWhere ){
if( sqliteExprResolveIds(pParse, pTabList, 0, pWhere) ){
goto update_cleanup;
}
if( sqliteExprCheck(pParse, pWhere, 0, 0) ){
goto update_cleanup;
}
}
/* Start the view context
*/
if( isView ){
sqliteAuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqliteGetVdbe(pParse);
if( v==0 ) goto update_cleanup;
sqliteBeginWriteOperation(pParse, 1, pTab->iDb);
/* If we are trying to update a view, construct that view into
** a temporary table.
*/
if( isView ){
Select *pView;
pView = sqliteSelectDup(pTab->pSelect);
sqliteSelect(pParse, pView, SRT_TempTable, iCur, 0, 0, 0);
sqliteSelectDelete(pView);
}
/* Begin the database scan
*/
pWInfo = sqliteWhereBegin(pParse, pTabList, pWhere, 1, 0);
if( pWInfo==0 ) goto update_cleanup;
/* Remember the index of every item to be updated.
*/
sqliteVdbeAddOp(v, OP_ListWrite, 0, 0);
/* End the database scan loop.
*/
sqliteWhereEnd(pWInfo);
/* Initialize the count of updated rows
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
sqliteVdbeAddOp(v, OP_Integer, 0, 0);
}
if( row_triggers_exist ){
/* Create pseudo-tables for NEW and OLD
*/
sqliteVdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
sqliteVdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
/* The top of the update loop for when there are triggers.
*/
sqliteVdbeAddOp(v, OP_ListRewind, 0, 0);
addr = sqliteVdbeAddOp(v, OP_ListRead, 0, 0);
sqliteVdbeAddOp(v, OP_Dup, 0, 0);
/* Open a cursor and make it point to the record that is
** being updated.
*/
sqliteVdbeAddOp(v, OP_Dup, 0, 0);
if( !isView ){
sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
sqliteVdbeAddOp(v, OP_OpenRead, iCur, pTab->tnum);
}
sqliteVdbeAddOp(v, OP_MoveTo, iCur, 0);
/* Generate the OLD table
*/
sqliteVdbeAddOp(v, OP_Recno, iCur, 0);
sqliteVdbeAddOp(v, OP_RowData, iCur, 0);
sqliteVdbeAddOp(v, OP_PutIntKey, oldIdx, 0);
/* Generate the NEW table
*/
if( chngRecno ){
sqliteExprCode(pParse, pRecnoExpr);
}else{
sqliteVdbeAddOp(v, OP_Recno, iCur, 0);
}
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqliteVdbeAddOp(v, OP_String, 0, 0);
continue;
}
j = aXRef[i];
if( j<0 ){
sqliteVdbeAddOp(v, OP_Column, iCur, i);
}else{
sqliteExprCode(pParse, pChanges->a[j].pExpr);
}
}
sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
sqliteVdbeAddOp(v, OP_PutIntKey, newIdx, 0);
if( !isView ){
sqliteVdbeAddOp(v, OP_Close, iCur, 0);
}
/* Fire the BEFORE and INSTEAD OF triggers
*/
if( sqliteCodeRowTrigger(pParse, TK_UPDATE, pChanges, TK_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.
*/
sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
sqliteVdbeAddOp(v, OP_OpenWrite, iCur, pTab->tnum);
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] ){
sqliteVdbeAddOp(v, OP_Integer, pIdx->iDb, 0);
sqliteVdbeAddOp(v, OP_OpenWrite, iCur+i+1, pIdx->tnum);
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( !row_triggers_exist ){
sqliteVdbeAddOp(v, OP_ListRewind, 0, 0);
addr = sqliteVdbeAddOp(v, OP_ListRead, 0, 0);
sqliteVdbeAddOp(v, OP_Dup, 0, 0);
}
sqliteVdbeAddOp(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 ){
sqliteExprCode(pParse, pRecnoExpr);
sqliteVdbeAddOp(v, OP_MustBeInt, 0, 0);
}
/* Compute new data for this record.
*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqliteVdbeAddOp(v, OP_String, 0, 0);
continue;
}
j = aXRef[i];
if( j<0 ){
sqliteVdbeAddOp(v, OP_Column, iCur, i);
}else{
sqliteExprCode(pParse, pChanges->a[j].pExpr);
}
}
/* Do constraint checks
*/
sqliteGenerateConstraintChecks(pParse, pTab, iCur, aIdxUsed, chngRecno, 1,
onError, addr);
/* Delete the old indices for the current record.
*/
sqliteGenerateRowIndexDelete(db, v, pTab, iCur, aIdxUsed);
/* If changing the record number, delete the old record.
*/
if( chngRecno ){
sqliteVdbeAddOp(v, OP_Delete, iCur, 0);
}
/* Create the new index entries and the new record.
*/
sqliteCompleteInsertion(pParse, pTab, iCur, aIdxUsed, chngRecno, 1, -1);
}
/* Increment the row counter
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack){
sqliteVdbeAddOp(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( row_triggers_exist ){
if( !isView ){
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] )
sqliteVdbeAddOp(v, OP_Close, iCur+i+1, 0);
}
sqliteVdbeAddOp(v, OP_Close, iCur, 0);
pParse->nTab = iCur;
}
if( sqliteCodeRowTrigger(pParse, TK_UPDATE, pChanges, TK_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.
*/
sqliteVdbeAddOp(v, OP_Goto, 0, addr);
sqliteVdbeChangeP2(v, addr, sqliteVdbeCurrentAddr(v));
sqliteVdbeAddOp(v, OP_ListReset, 0, 0);
/* Close all tables if there were no FOR EACH ROW triggers */
if( !row_triggers_exist ){
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] ){
sqliteVdbeAddOp(v, OP_Close, iCur+i+1, 0);
}
}
sqliteVdbeAddOp(v, OP_Close, iCur, 0);
pParse->nTab = iCur;
}else{
sqliteVdbeAddOp(v, OP_Close, newIdx, 0);
sqliteVdbeAddOp(v, OP_Close, oldIdx, 0);
}
sqliteVdbeAddOp(v, OP_SetCounts, 0, 0);
sqliteEndWriteOperation(pParse);
/*
** Return the number of rows that were changed.
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
sqliteVdbeOp3(v, OP_ColumnName, 0, 1, "rows updated", P3_STATIC);
sqliteVdbeAddOp(v, OP_Callback, 1, 0);
}
update_cleanup:
sqliteAuthContextPop(&sContext);
sqliteFree(apIdx);
sqliteFree(aXRef);
sqliteSrcListDelete(pTabList);
sqliteExprListDelete(pChanges);
sqliteExprDelete(pWhere);
return;
}
/*
** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up
** that name in the set of source tables in pSrcList and make the pExpr
** expression node refer back to that source column. The following changes
** are made to pExpr:
**
** pExpr->iDb Set the index in db->aDb[] of the database holding
** the table.
** pExpr->iTable Set to the cursor number for the table obtained
** from pSrcList.
** pExpr->iColumn Set to the column number within the table.
** pExpr->dataType Set to the appropriate data type for the column.
** pExpr->op Set to TK_COLUMN.
** pExpr->pLeft Any expression this points to is deleted
** pExpr->pRight Any expression this points to is deleted.
**
** The pDbToken is the name of the database (the "X"). This value may be
** NULL meaning that name is of the form Y.Z or Z. Any available database
** can be used. The pTableToken is the name of the table (the "Y"). This
** value can be NULL if pDbToken is also NULL. If pTableToken is NULL it
** means that the form of the name is Z and that columns from any table
** can be used.
**
** If the name cannot be resolved unambiguously, leave an error message
** in pParse and return non-zero. Return zero on success.
*/
static int lookupName(
Parse *pParse, /* The parsing context */
Token *pDbToken, /* Name of the database containing table, or NULL */
Token *pTableToken, /* Name of table containing column, or NULL */
Token *pColumnToken, /* Name of the column. */
SrcList *pSrcList, /* List of tables used to resolve column names */
ExprList *pEList, /* List of expressions used to resolve "AS" */
Expr *pExpr /* Make this EXPR node point to the selected column */
){
char *zDb = 0; /* Name of the database. The "X" in X.Y.Z */
char *zTab = 0; /* Name of the table. The "Y" in X.Y.Z or Y.Z */
char *zCol = 0; /* Name of the column. The "Z" */
int i, j; /* Loop counters */
int cnt = 0; /* Number of matching column names */
int cntTab = 0; /* Number of matching table names */
sqlite *db = pParse->db; /* The database */
assert( pColumnToken && pColumnToken->z ); /* The Z in X.Y.Z cannot be NULL */
if( pDbToken && pDbToken->z ){
zDb = sqliteStrNDup(pDbToken->z, pDbToken->n);
sqliteDequote(zDb);
}else{
zDb = 0;
}
if( pTableToken && pTableToken->z ){
zTab = sqliteStrNDup(pTableToken->z, pTableToken->n);
sqliteDequote(zTab);
}else{
assert( zDb==0 );
zTab = 0;
}
zCol = sqliteStrNDup(pColumnToken->z, pColumnToken->n);
sqliteDequote(zCol);
if( sqlite_malloc_failed ){
return 1; /* Leak memory (zDb and zTab) if malloc fails */
}
assert( zTab==0 || pEList==0 );
pExpr->iTable = -1;
for(i=0; i<pSrcList->nSrc; i++){
struct SrcList_item *pItem = &pSrcList->a[i];
Table *pTab = pItem->pTab;
Column *pCol;
if( pTab==0 ) continue;
assert( pTab->nCol>0 );
if( zTab ){
if( pItem->zAlias ){
char *zTabName = pItem->zAlias;
if( sqliteStrICmp(zTabName, zTab)!=0 ) continue;
}else{
char *zTabName = pTab->zName;
if( zTabName==0 || sqliteStrICmp(zTabName, zTab)!=0 ) continue;
if( zDb!=0 && sqliteStrICmp(db->aDb[pTab->iDb].zName, zDb)!=0 ){
continue;
}
}
}
if( 0==(cntTab++) ){
pExpr->iTable = pItem->iCursor;
pExpr->iDb = pTab->iDb;
}
for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
if( sqliteStrICmp(pCol->zName, zCol)==0 ){
cnt++;
pExpr->iTable = pItem->iCursor;
pExpr->iDb = pTab->iDb;
/* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
pExpr->iColumn = j==pTab->iPKey ? -1 : j;
pExpr->dataType = pCol->sortOrder & SQLITE_SO_TYPEMASK;
break;
}
}
}
/* If we have not already resolved the name, then maybe
** it is a new.* or old.* trigger argument reference
*/
if( zDb==0 && zTab!=0 && cnt==0 && pParse->trigStack!=0 ){
TriggerStack *pTriggerStack = pParse->trigStack;
Table *pTab = 0;
if( pTriggerStack->newIdx != -1 && sqliteStrICmp("new", zTab) == 0 ){
pExpr->iTable = pTriggerStack->newIdx;
assert( pTriggerStack->pTab );
pTab = pTriggerStack->pTab;
}else if( pTriggerStack->oldIdx != -1 && sqliteStrICmp("old", zTab) == 0 ){
pExpr->iTable = pTriggerStack->oldIdx;
assert( pTriggerStack->pTab );
pTab = pTriggerStack->pTab;
}
if( pTab ){
int j;
Column *pCol = pTab->aCol;
pExpr->iDb = pTab->iDb;
cntTab++;
for(j=0; j < pTab->nCol; j++, pCol++) {
if( sqliteStrICmp(pCol->zName, zCol)==0 ){
cnt++;
pExpr->iColumn = j==pTab->iPKey ? -1 : j;
pExpr->dataType = pCol->sortOrder & SQLITE_SO_TYPEMASK;
break;
}
}
}
}
/*
** Perhaps the name is a reference to the ROWID
*/
if( cnt==0 && cntTab==1 && sqliteIsRowid(zCol) ){
cnt = 1;
pExpr->iColumn = -1;
pExpr->dataType = SQLITE_SO_NUM;
}
/*
** If the input is of the form Z (not Y.Z or X.Y.Z) then the name Z
** might refer to an result-set alias. This happens, for example, when
** we are resolving names in the WHERE clause of the following command:
**
** SELECT a+b AS x FROM table WHERE x<10;
**
** In cases like this, replace pExpr with a copy of the expression that
** forms the result set entry ("a+b" in the example) and return immediately.
** Note that the expression in the result set should have already been
** resolved by the time the WHERE clause is resolved.
*/
if( cnt==0 && pEList!=0 ){
for(j=0; j<pEList->nExpr; j++){
char *zAs = pEList->a[j].zName;
if( zAs!=0 && sqliteStrICmp(zAs, zCol)==0 ){
assert( pExpr->pLeft==0 && pExpr->pRight==0 );
pExpr->op = TK_AS;
pExpr->iColumn = j;
pExpr->pLeft = sqliteExprDup(pEList->a[j].pExpr);
sqliteFree(zCol);
assert( zTab==0 && zDb==0 );
return 0;
}
}
}
/*
** If X and Y are NULL (in other words if only the column name Z is
** supplied) and the value of Z is enclosed in double-quotes, then
** Z is a string literal if it doesn't match any column names. In that
** case, we need to return right away and not make any changes to
** pExpr.
*/
if( cnt==0 && zTab==0 && pColumnToken->z[0]=='"' ){
sqliteFree(zCol);
return 0;
}
/*
** cnt==0 means there was not match. cnt>1 means there were two or
** more matches. Either way, we have an error.
*/
if( cnt!=1 ){
char *z = 0;
char *zErr;
zErr = cnt==0 ? "no such column: %s" : "ambiguous column name: %s";
if( zDb ){
sqliteSetString(&z, zDb, ".", zTab, ".", zCol, 0);
}else if( zTab ){
sqliteSetString(&z, zTab, ".", zCol, 0);
}else{
z = sqliteStrDup(zCol);
}
sqliteErrorMsg(pParse, zErr, z);
sqliteFree(z);
}
/* Clean up and return
*/
sqliteFree(zDb);
sqliteFree(zTab);
sqliteFree(zCol);
sqliteExprDelete(pExpr->pLeft);
pExpr->pLeft = 0;
sqliteExprDelete(pExpr->pRight);
pExpr->pRight = 0;
pExpr->op = TK_COLUMN;
sqliteAuthRead(pParse, pExpr, pSrcList);
return cnt!=1;
}
