diff options
Diffstat (limited to 'components/external/SQLite-3.8.1/src/update.c')
| -rw-r--r-- | components/external/SQLite-3.8.1/src/update.c | 675 |
1 files changed, 0 insertions, 675 deletions
diff --git a/components/external/SQLite-3.8.1/src/update.c b/components/external/SQLite-3.8.1/src/update.c deleted file mode 100644 index 0f760a4609..0000000000 --- a/components/external/SQLite-3.8.1/src/update.c +++ /dev/null @@ -1,675 +0,0 @@ -/* -** 2001 September 15 -** -** The author disclaims copyright to this source code. In place of -** a legal notice, here is a blessing: -** -** May you do good and not evil. -** May you find forgiveness for yourself and forgive others. -** May you share freely, never taking more than you give. -** -************************************************************************* -** This file contains C code routines that are called by the parser -** to handle UPDATE statements. -*/ -#include "sqliteInt.h" - -#ifndef SQLITE_OMIT_VIRTUALTABLE -/* Forward declaration */ -static void updateVirtualTable( - Parse *pParse, /* The parsing context */ - SrcList *pSrc, /* The virtual table to be modified */ - Table *pTab, /* The virtual table */ - ExprList *pChanges, /* The columns to change in the UPDATE statement */ - Expr *pRowidExpr, /* Expression used to recompute the rowid */ - int *aXRef, /* Mapping from columns of pTab to entries in pChanges */ - Expr *pWhere, /* WHERE clause of the UPDATE statement */ - int onError /* ON CONFLICT strategy */ -); -#endif /* SQLITE_OMIT_VIRTUALTABLE */ - -/* -** The most recently coded instruction was an OP_Column to retrieve the -** i-th column of table pTab. This routine sets the P4 parameter of the -** OP_Column to the default value, if any. -** -** The default value of a column is specified by a DEFAULT clause in the -** column definition. This was either supplied by the user when the table -** was created, or added later to the table definition by an ALTER TABLE -** command. If the latter, then the row-records in the table btree on disk -** may not contain a value for the column and the default value, taken -** from the P4 parameter of the OP_Column instruction, is returned instead. -** If the former, then all row-records are guaranteed to include a value -** for the column and the P4 value is not required. -** -** Column definitions created by an ALTER TABLE command may only have -** literal default values specified: a number, null or a string. (If a more -** complicated default expression value was provided, it is evaluated -** when the ALTER TABLE is executed and one of the literal values written -** into the sqlite_master table.) -** -** Therefore, the P4 parameter is only required if the default value for -** the column is a literal number, string or null. The sqlite3ValueFromExpr() -** function is capable of transforming these types of expressions into -** sqlite3_value objects. -** -** If parameter iReg is not negative, code an OP_RealAffinity instruction -** on register iReg. This is used when an equivalent integer value is -** stored in place of an 8-byte floating point value in order to save -** space. -*/ -void sqlite3ColumnDefault(Vdbe *v, Table *pTab, int i, int iReg){ - assert( pTab!=0 ); - if( !pTab->pSelect ){ - sqlite3_value *pValue = 0; - u8 enc = ENC(sqlite3VdbeDb(v)); - Column *pCol = &pTab->aCol[i]; - VdbeComment((v, "%s.%s", pTab->zName, pCol->zName)); - assert( i<pTab->nCol ); - sqlite3ValueFromExpr(sqlite3VdbeDb(v), pCol->pDflt, enc, - pCol->affinity, &pValue); - if( pValue ){ - sqlite3VdbeChangeP4(v, -1, (const char *)pValue, P4_MEM); - } -#ifndef SQLITE_OMIT_FLOATING_POINT - if( iReg>=0 && pTab->aCol[i].affinity==SQLITE_AFF_REAL ){ - sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg); - } -#endif - } -} - -/* -** 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; /* 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 */ - - 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) ){ - 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 - } - - 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( hasFK || chngRowid || pIdx->pPartIdxWhere ){ - 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, onError); - pWhere = 0; - pTabList = 0; - goto update_cleanup; - } -#endif - - /* Allocate required registers. */ - regRowSet = ++pParse->nMem; - 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; - - /* 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 - */ - sqlite3VdbeAddOp3(v, OP_Null, 0, regRowSet, regOldRowid); - pWInfo = sqlite3WhereBegin( - pParse, pTabList, pWhere, 0, 0, WHERE_ONEPASS_DESIRED, 0 - ); - if( pWInfo==0 ) goto update_cleanup; - okOnePass = sqlite3WhereOkOnePass(pWInfo); - - /* Remember the rowid of every item to be updated. - */ - sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regOldRowid); - if( !okOnePass ){ - 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++){ - assert( aRegIdx ); - 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 || (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); - } - } - - /* Populate the array of registers beginning at regNew with the new - ** row data. This array is used to check constaints, create the new - ** table and index records, and as the values for any new.* references - ** made by triggers. - ** - ** If there are one or more BEFORE triggers, then do not populate the - ** registers associated with columns that are (a) not modified by - ** this UPDATE statement and (b) not accessed by new.* references. The - ** values for registers not modified by the UPDATE must be reloaded from - ** the database after the BEFORE triggers are fired anyway (as the trigger - ** may have modified them). So not loading those that are not going to - ** be used eliminates some redundant opcodes. - */ - newmask = sqlite3TriggerColmask( - pParse, pTrigger, pChanges, 1, TRIGGER_BEFORE, pTab, onError - ); - sqlite3VdbeAddOp3(v, OP_Null, 0, regNew, regNew+pTab->nCol-1); - for(i=0; i<pTab->nCol; i++){ - if( i==pTab->iPKey ){ - /*sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);*/ - }else{ - j = aXRef[i]; - if( j>=0 ){ - sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regNew+i); - }else if( 0==(tmask&TRIGGER_BEFORE) || i>31 || (newmask&(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 behavior - 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, aXRef, chngRowid); - } - - /* 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, aXRef, chngRowid); - } - - /* 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, aXRef, chngRowid); - } - } - - /* 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++){ - assert( aRegIdx ); - 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; -} -/* Make sure "isView" and other macros defined above are undefined. Otherwise -** thely may interfere with compilation of other functions in this file -** (or in another file, if this file becomes part of the amalgamation). */ -#ifdef isView - #undef isView -#endif -#ifdef pTrigger - #undef pTrigger -#endif - -#ifndef SQLITE_OMIT_VIRTUALTABLE -/* -** Generate code for an UPDATE of a virtual table. -** -** The strategy is that we create an ephemerial table that contains -** for each row to be changed: -** -** (A) The original rowid of that row. -** (B) The revised rowid for the row. (note1) -** (C) The content of every column in the row. -** -** Then we loop over this ephemeral table and for each row in -** the ephermeral table call VUpdate. -** -** When finished, drop the ephemeral table. -** -** (note1) Actually, if we know in advance that (A) is always the same -** as (B) we only store (A), then duplicate (A) when pulling -** it out of the ephemeral table before calling VUpdate. -*/ -static void updateVirtualTable( - Parse *pParse, /* The parsing context */ - SrcList *pSrc, /* The virtual table to be modified */ - Table *pTab, /* The virtual table */ - ExprList *pChanges, /* The columns to change in the UPDATE statement */ - Expr *pRowid, /* Expression used to recompute the rowid */ - int *aXRef, /* Mapping from columns of pTab to entries in pChanges */ - Expr *pWhere, /* WHERE clause of the UPDATE statement */ - int onError /* ON CONFLICT strategy */ -){ - Vdbe *v = pParse->pVdbe; /* Virtual machine under construction */ - ExprList *pEList = 0; /* The result set of the SELECT statement */ - Select *pSelect = 0; /* The SELECT statement */ - Expr *pExpr; /* Temporary expression */ - int ephemTab; /* Table holding the result of the SELECT */ - int i; /* Loop counter */ - int addr; /* Address of top of loop */ - int iReg; /* First register in set passed to OP_VUpdate */ - sqlite3 *db = pParse->db; /* Database connection */ - const char *pVTab = (const char*)sqlite3GetVTable(db, pTab); - SelectDest dest; - - /* Construct the SELECT statement that will find the new values for - ** all updated rows. - */ - pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db, TK_ID, "_rowid_")); - if( pRowid ){ - pEList = sqlite3ExprListAppend(pParse, pEList, - sqlite3ExprDup(db, pRowid, 0)); - } - assert( pTab->iPKey<0 ); - for(i=0; i<pTab->nCol; i++){ - if( aXRef[i]>=0 ){ - pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr, 0); - }else{ - pExpr = sqlite3Expr(db, TK_ID, pTab->aCol[i].zName); - } - pEList = sqlite3ExprListAppend(pParse, pEList, pExpr); - } - pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0); - - /* Create the ephemeral table into which the update results will - ** be stored. - */ - assert( v ); - ephemTab = pParse->nTab++; - sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0)); - sqlite3VdbeChangeP5(v, BTREE_UNORDERED); - - /* fill the ephemeral table - */ - sqlite3SelectDestInit(&dest, SRT_Table, ephemTab); - sqlite3Select(pParse, pSelect, &dest); - - /* Generate code to scan the ephemeral table and call VUpdate. */ - iReg = ++pParse->nMem; - pParse->nMem += pTab->nCol+1; - addr = sqlite3VdbeAddOp2(v, OP_Rewind, ephemTab, 0); - sqlite3VdbeAddOp3(v, OP_Column, ephemTab, 0, iReg); - sqlite3VdbeAddOp3(v, OP_Column, ephemTab, (pRowid?1:0), iReg+1); - for(i=0; i<pTab->nCol; i++){ - sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i); - } - sqlite3VtabMakeWritable(pParse, pTab); - sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVTab, P4_VTAB); - sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError); - sqlite3MayAbort(pParse); - sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1); - sqlite3VdbeJumpHere(v, addr); - sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0); - - /* Cleanup */ - sqlite3SelectDelete(db, pSelect); -} -#endif /* SQLITE_OMIT_VIRTUALTABLE */ |