/* ** Construct and install a Module object for a virtual table. When this ** routine is called, it is guaranteed that all appropriate locks are held ** and the module is not already part of the connection. */ Module *sqlite3VtabCreateModule( sqlite3 *db, /* Database in which module is registered */ const char *zName, /* Name assigned to this module */ const sqlite3_module *pModule, /* The definition of the module */ void *pAux, /* Context pointer for xCreate/xConnect */ void (*xDestroy)(void *) /* Module destructor function */ ){ Module *pMod; int nName = sqlite3Strlen30(zName); pMod = (Module *)sqlite3DbMallocRawNN(db, sizeof(Module) + nName + 1); if( pMod ){ Module *pDel; char *zCopy = (char *)(&pMod[1]); memcpy(zCopy, zName, nName+1); pMod->zName = zCopy; pMod->pModule = pModule; pMod->pAux = pAux; pMod->xDestroy = xDestroy; pMod->pEpoTab = 0; pDel = (Module *)sqlite3HashInsert(&db->aModule,zCopy,(void*)pMod); assert( pDel==0 || pDel==pMod ); if( pDel ){ sqlite3OomFault(db); sqlite3DbFree(db, pDel); pMod = 0; } } return pMod; }
static SQLITE_NOINLINE void *dbReallocFinish(sqlite3 *db, void *p, u64 n){ void *pNew = 0; assert( db!=0 ); assert( p!=0 ); if( db->mallocFailed==0 ){ if( isLookaside(db, p) ){ pNew = sqlite3DbMallocRawNN(db, n); if( pNew ){ memcpy(pNew, p, db->lookaside.sz); sqlite3DbFree(db, p); } }else{ assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) ); assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) ); sqlite3MemdebugSetType(p, MEMTYPE_HEAP); pNew = sqlite3_realloc64(p, n); if( !pNew ){ sqlite3OomFault(db); } sqlite3MemdebugSetType(pNew, (db->lookaside.bDisable==0 ? MEMTYPE_LOOKASIDE : MEMTYPE_HEAP)); } } return pNew; }
/* ** Allocate memory, either lookaside (if possible) or heap. ** If the allocation fails, set the mallocFailed flag in ** the connection pointer. ** ** If db!=0 and db->mallocFailed is true (indicating a prior malloc ** failure on the same database connection) then always return 0. ** Hence for a particular database connection, once malloc starts ** failing, it fails consistently until mallocFailed is reset. ** This is an important assumption. There are many places in the ** code that do things like this: ** ** int *a = (int*)sqlite3DbMallocRaw(db, 100); ** int *b = (int*)sqlite3DbMallocRaw(db, 200); ** if( b ) a[10] = 9; ** ** In other words, if a subsequent malloc (ex: "b") worked, it is assumed ** that all prior mallocs (ex: "a") worked too. ** ** The sqlite3MallocRawNN() variant guarantees that the "db" parameter is ** not a NULL pointer. */ void *sqlite3DbMallocRaw(sqlite3 *db, u64 n){ void *p; if( db ) return sqlite3DbMallocRawNN(db, n); p = sqlite3Malloc(n); sqlite3MemdebugSetType(p, MEMTYPE_HEAP); return p; }
/* ** Resize the block of memory pointed to by p to n bytes. If the ** resize fails, set the mallocFailed flag in the connection object. */ void *sqlite3DbRealloc(sqlite3 *db, void *p, u64 n){ assert( db!=0 ); if( p==0 ) return sqlite3DbMallocRawNN(db, n); assert( sqlite3_mutex_held(db->mutex) ); if( isLookaside(db,p) && n<=db->lookaside.sz ) return p; return dbReallocFinish(db, p, n); }
char *sqlite3DbStrNDup(sqlite3 *db, const char *z, u64 n){ char *zNew; assert( db!=0 ); if( z==0 ){ return 0; } assert( (n&0x7fffffff)==n ); zNew = sqlite3DbMallocRawNN(db, n+1); if( zNew ){ memcpy(zNew, z, (size_t)n); zNew[n] = 0; } return zNew; }
/* ** Allocate a new RowSetEntry object that is associated with the ** given RowSet. Return a pointer to the new and completely uninitialized ** objected. ** ** In an OOM situation, the RowSet.db->mallocFailed flag is set and this ** routine returns NULL. */ static struct RowSetEntry *rowSetEntryAlloc(RowSet *p){ assert( p!=0 ); if( p->nFresh==0 ){ struct RowSetChunk *pNew; pNew = sqlite3DbMallocRawNN(p->db, sizeof(*pNew)); if( pNew==0 ){ return 0; } pNew->pNextChunk = p->pChunk; p->pChunk = pNew; p->pFresh = pNew->aEntry; p->nFresh = ROWSET_ENTRY_PER_CHUNK; } p->nFresh--; return p->pFresh++; }
/* ** Allocate a new RowSetEntry object that is associated with the ** given RowSet. Return a pointer to the new and completely uninitialized ** objected. ** ** In an OOM situation, the RowSet.db->mallocFailed flag is set and this ** routine returns NULL. */ static struct RowSetEntry *rowSetEntryAlloc(RowSet *p){ assert( p!=0 ); if( p->nFresh==0 ){ /*OPTIMIZATION-IF-FALSE*/ /* We could allocate a fresh RowSetEntry each time one is needed, but it ** is more efficient to pull a preallocated entry from the pool */ struct RowSetChunk *pNew; pNew = sqlite3DbMallocRawNN(p->db, sizeof(*pNew)); if( pNew==0 ){ return 0; } pNew->pNextChunk = p->pChunk; p->pChunk = pNew; p->pFresh = pNew->aEntry; p->nFresh = ROWSET_ENTRY_PER_CHUNK; } p->nFresh--; return p->pFresh++; }
/* ** The actual function that does the work of creating a new module. ** This function implements the sqlite3_create_module() and ** sqlite3_create_module_v2() interfaces. */ static int createModule( sqlite3 *db, /* Database in which module is registered */ const char *zName, /* Name assigned to this module */ const sqlite3_module *pModule, /* The definition of the module */ void *pAux, /* Context pointer for xCreate/xConnect */ void (*xDestroy)(void *) /* Module destructor function */ ){ int rc = SQLITE_OK; int nName; sqlite3_mutex_enter(db->mutex); nName = sqlite3Strlen30(zName); if( sqlite3HashFind(&db->aModule, zName) ){ rc = SQLITE_MISUSE_BKPT; }else{ Module *pMod; pMod = (Module *)sqlite3DbMallocRawNN(db, sizeof(Module) + nName + 1); if( pMod ){ Module *pDel; char *zCopy = (char *)(&pMod[1]); memcpy(zCopy, zName, nName+1); pMod->zName = zCopy; pMod->pModule = pModule; pMod->pAux = pAux; pMod->xDestroy = xDestroy; pMod->pEpoTab = 0; pDel = (Module *)sqlite3HashInsert(&db->aModule,zCopy,(void*)pMod); assert( pDel==0 || pDel==pMod ); if( pDel ){ sqlite3OomFault(db); sqlite3DbFree(db, pDel); } } } rc = sqlite3ApiExit(db, rc); if( rc!=SQLITE_OK && xDestroy ) xDestroy(pAux); sqlite3_mutex_leave(db->mutex); return rc; }
/* ** Generate code for a DELETE FROM statement. ** ** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL; ** \________/ \________________/ ** pTabList pWhere */ void sqlite3DeleteFrom( Parse *pParse, /* The parser context */ SrcList *pTabList, /* The table from which we should delete things */ Expr *pWhere /* The WHERE clause. May be null */ ){ Vdbe *v; /* The virtual database engine */ Table *pTab; /* The table from which records will be deleted */ int i; /* Loop counter */ WhereInfo *pWInfo; /* Information about the WHERE clause */ Index *pIdx; /* For looping over indices of the table */ int iTabCur; /* Cursor number for the table */ int iDataCur = 0; /* VDBE cursor for the canonical data source */ int iIdxCur = 0; /* Cursor number of the first index */ int nIdx; /* Number of indices */ sqlite3 *db; /* Main database structure */ AuthContext sContext; /* Authorization context */ NameContext sNC; /* Name context to resolve expressions in */ int iDb; /* Database number */ int memCnt = -1; /* Memory cell used for change counting */ int rcauth; /* Value returned by authorization callback */ int eOnePass; /* ONEPASS_OFF or _SINGLE or _MULTI */ int aiCurOnePass[2]; /* The write cursors opened by WHERE_ONEPASS */ u8 *aToOpen = 0; /* Open cursor iTabCur+j if aToOpen[j] is true */ Index *pPk; /* The PRIMARY KEY index on the table */ int iPk = 0; /* First of nPk registers holding PRIMARY KEY value */ i16 nPk = 1; /* Number of columns in the PRIMARY KEY */ int iKey; /* Memory cell holding key of row to be deleted */ i16 nKey; /* Number of memory cells in the row key */ int iEphCur = 0; /* Ephemeral table holding all primary key values */ int iRowSet = 0; /* Register for rowset of rows to delete */ int addrBypass = 0; /* Address of jump over the delete logic */ int addrLoop = 0; /* Top of the delete loop */ int addrEphOpen = 0; /* Instruction to open the Ephemeral table */ int bComplex; /* True if there are triggers or FKs or ** subqueries in the WHERE clause */ #ifndef SQLITE_OMIT_TRIGGER int isView; /* True if attempting to delete from a view */ Trigger *pTrigger; /* List of table triggers, if required */ #endif memset(&sContext, 0, sizeof(sContext)); db = pParse->db; if( pParse->nErr || db->mallocFailed ){ goto delete_from_cleanup; } assert( pTabList->nSrc==1 ); /* Locate the table which we want to delete. This table has to be ** put in an SrcList structure because some of the subroutines we ** will be calling are designed to work with multiple tables and expect ** an SrcList* parameter instead of just a Table* parameter. */ pTab = sqlite3SrcListLookup(pParse, pTabList); if( pTab==0 ) goto delete_from_cleanup; /* Figure out if we have any triggers and if the table being ** deleted from is a view */ #ifndef SQLITE_OMIT_TRIGGER pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0); isView = pTab->pSelect!=0; bComplex = pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0); #else # define pTrigger 0 # define isView 0 #endif #ifdef SQLITE_OMIT_VIEW # undef isView # define isView 0 #endif /* If pTab is really a view, make sure it has been initialized. */ if( sqlite3ViewGetColumnNames(pParse, pTab) ){ goto delete_from_cleanup; } if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){ goto delete_from_cleanup; } iDb = sqlite3SchemaToIndex(db, pTab->pSchema); assert( iDb<db->nDb ); rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, db->aDb[iDb].zDbSName); assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE ); if( rcauth==SQLITE_DENY ){ goto delete_from_cleanup; } assert(!isView || pTrigger); /* Assign cursor numbers to the table and all its indices. */ assert( pTabList->nSrc==1 ); iTabCur = pTabList->a[0].iCursor = pParse->nTab++; for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){ pParse->nTab++; } /* Start the view context */ if( isView ){ sqlite3AuthContextPush(pParse, &sContext, pTab->zName); } /* Begin generating code. */ v = sqlite3GetVdbe(pParse); if( v==0 ){ goto delete_from_cleanup; } if( pParse->nested==0 ) sqlite3VdbeCountChanges(v); sqlite3BeginWriteOperation(pParse, 1, iDb); /* If we are trying to delete from a view, realize that view into ** an ephemeral table. */ #if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) if( isView ){ sqlite3MaterializeView(pParse, pTab, pWhere, iTabCur); iDataCur = iIdxCur = iTabCur; } #endif /* Resolve the column names in the WHERE clause. */ memset(&sNC, 0, sizeof(sNC)); sNC.pParse = pParse; sNC.pSrcList = pTabList; if( sqlite3ResolveExprNames(&sNC, pWhere) ){ goto delete_from_cleanup; } /* Initialize the counter of the number of rows deleted, if ** we are counting rows. */ if( db->flags & SQLITE_CountRows ){ memCnt = ++pParse->nMem; sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt); } #ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION /* Special case: A DELETE without a WHERE clause deletes everything. ** It is easier just to erase the whole table. Prior to version 3.6.5, ** this optimization caused the row change count (the value returned by ** API function sqlite3_count_changes) to be set incorrectly. */ if( rcauth==SQLITE_OK && pWhere==0 && !bComplex && !IsVirtual(pTab) #ifdef SQLITE_ENABLE_PREUPDATE_HOOK && db->xPreUpdateCallback==0 #endif ){ assert( !isView ); sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName); if( HasRowid(pTab) ){ sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt, pTab->zName, P4_STATIC); } for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){ assert( pIdx->pSchema==pTab->pSchema ); sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb); } }else #endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */ { u16 wcf = WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK|WHERE_SEEK_TABLE; if( sNC.ncFlags & NC_VarSelect ) bComplex = 1; wcf |= (bComplex ? 0 : WHERE_ONEPASS_MULTIROW); if( HasRowid(pTab) ){ /* For a rowid table, initialize the RowSet to an empty set */ pPk = 0; nPk = 1; iRowSet = ++pParse->nMem; sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet); }else{ /* For a WITHOUT ROWID table, create an ephemeral table used to ** hold all primary keys for rows to be deleted. */ pPk = sqlite3PrimaryKeyIndex(pTab); assert( pPk!=0 ); nPk = pPk->nKeyCol; iPk = pParse->nMem+1; pParse->nMem += nPk; iEphCur = pParse->nTab++; addrEphOpen = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEphCur, nPk); sqlite3VdbeSetP4KeyInfo(pParse, pPk); } /* Construct a query to find the rowid or primary key for every row ** to be deleted, based on the WHERE clause. Set variable eOnePass ** to indicate the strategy used to implement this delete: ** ** ONEPASS_OFF: Two-pass approach - use a FIFO for rowids/PK values. ** ONEPASS_SINGLE: One-pass approach - at most one row deleted. ** ONEPASS_MULTI: One-pass approach - any number of rows may be deleted. */ pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0, wcf, iTabCur+1); if( pWInfo==0 ) goto delete_from_cleanup; eOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass); assert( IsVirtual(pTab)==0 || eOnePass!=ONEPASS_MULTI ); assert( IsVirtual(pTab) || bComplex || eOnePass!=ONEPASS_OFF ); /* Keep track of the number of rows to be deleted */ if( db->flags & SQLITE_CountRows ){ sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1); } /* Extract the rowid or primary key for the current row */ if( pPk ){ for(i=0; i<nPk; i++){ assert( pPk->aiColumn[i]>=0 ); sqlite3ExprCodeGetColumnOfTable(v, pTab, iTabCur, pPk->aiColumn[i], iPk+i); } iKey = iPk; }else{ iKey = pParse->nMem + 1; iKey = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iTabCur, iKey, 0); if( iKey>pParse->nMem ) pParse->nMem = iKey; } if( eOnePass!=ONEPASS_OFF ){ /* For ONEPASS, no need to store the rowid/primary-key. There is only ** one, so just keep it in its register(s) and fall through to the ** delete code. */ nKey = nPk; /* OP_Found will use an unpacked key */ aToOpen = sqlite3DbMallocRawNN(db, nIdx+2); if( aToOpen==0 ){ sqlite3WhereEnd(pWInfo); goto delete_from_cleanup; } memset(aToOpen, 1, nIdx+1); aToOpen[nIdx+1] = 0; if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iTabCur] = 0; if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iTabCur] = 0; if( addrEphOpen ) sqlite3VdbeChangeToNoop(v, addrEphOpen); }else{ if( pPk ){ /* Add the PK key for this row to the temporary table */ iKey = ++pParse->nMem; nKey = 0; /* Zero tells OP_Found to use a composite key */ sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey, sqlite3IndexAffinityStr(pParse->db, pPk), nPk); sqlite3VdbeAddOp2(v, OP_IdxInsert, iEphCur, iKey); }else{ /* Add the rowid of the row to be deleted to the RowSet */ nKey = 1; /* OP_Seek always uses a single rowid */ sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey); } } /* If this DELETE cannot use the ONEPASS strategy, this is the ** end of the WHERE loop */ if( eOnePass!=ONEPASS_OFF ){ addrBypass = sqlite3VdbeMakeLabel(v); }else{ sqlite3WhereEnd(pWInfo); } /* Unless this is a view, open cursors for the table we are ** deleting from and all its indices. If this is a view, then the ** only effect this statement has is to fire the INSTEAD OF ** triggers. */ if( !isView ){ int iAddrOnce = 0; if( eOnePass==ONEPASS_MULTI ){ iAddrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v); } testcase( IsVirtual(pTab) ); sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, OPFLAG_FORDELETE, iTabCur, aToOpen, &iDataCur, &iIdxCur); assert( pPk || IsVirtual(pTab) || iDataCur==iTabCur ); assert( pPk || IsVirtual(pTab) || iIdxCur==iDataCur+1 ); if( eOnePass==ONEPASS_MULTI ) sqlite3VdbeJumpHere(v, iAddrOnce); } /* Set up a loop over the rowids/primary-keys that were found in the ** where-clause loop above. */ if( eOnePass!=ONEPASS_OFF ){ assert( nKey==nPk ); /* OP_Found will use an unpacked key */ if( !IsVirtual(pTab) && aToOpen[iDataCur-iTabCur] ){ assert( pPk!=0 || pTab->pSelect!=0 ); sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, addrBypass, iKey, nKey); VdbeCoverage(v); } }else if( pPk ){ addrLoop = sqlite3VdbeAddOp1(v, OP_Rewind, iEphCur); VdbeCoverage(v); sqlite3VdbeAddOp2(v, OP_RowKey, iEphCur, iKey); assert( nKey==0 ); /* OP_Found will use a composite key */ }else{ addrLoop = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, 0, iKey); VdbeCoverage(v); assert( nKey==1 ); } /* Delete the row */ #ifndef SQLITE_OMIT_VIRTUALTABLE if( IsVirtual(pTab) ){ const char *pVTab = (const char *)sqlite3GetVTable(db, pTab); sqlite3VtabMakeWritable(pParse, pTab); sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iKey, pVTab, P4_VTAB); sqlite3VdbeChangeP5(v, OE_Abort); assert( eOnePass==ONEPASS_OFF || eOnePass==ONEPASS_SINGLE ); sqlite3MayAbort(pParse); if( eOnePass==ONEPASS_SINGLE && sqlite3IsToplevel(pParse) ){ pParse->isMultiWrite = 0; } }else #endif { int count = (pParse->nested==0); /* True to count changes */ int iIdxNoSeek = -1; if( bComplex==0 && aiCurOnePass[1]!=iDataCur ){ iIdxNoSeek = aiCurOnePass[1]; } sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur, iKey, nKey, count, OE_Default, eOnePass, iIdxNoSeek); } /* End of the loop over all rowids/primary-keys. */ if( eOnePass!=ONEPASS_OFF ){ sqlite3VdbeResolveLabel(v, addrBypass); sqlite3WhereEnd(pWInfo); }else if( pPk ){ sqlite3VdbeAddOp2(v, OP_Next, iEphCur, addrLoop+1); VdbeCoverage(v); sqlite3VdbeJumpHere(v, addrLoop); }else{ sqlite3VdbeGoto(v, addrLoop); sqlite3VdbeJumpHere(v, addrLoop); } /* Close the cursors open on the table and its indexes. */ if( !isView && !IsVirtual(pTab) ){ if( !pPk ) sqlite3VdbeAddOp1(v, OP_Close, iDataCur); for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){ sqlite3VdbeAddOp1(v, OP_Close, iIdxCur + i); } } } /* End non-truncate path */ /* Update the sqlite_sequence table by storing the content of the ** maximum rowid counter values recorded while inserting into ** autoincrement tables. */ if( pParse->nested==0 && pParse->pTriggerTab==0 ){ sqlite3AutoincrementEnd(pParse); } /* Return the number of rows that were deleted. If this routine is ** generating code because of a call to sqlite3NestedParse(), do not ** invoke the callback function. */ if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){ sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1); sqlite3VdbeSetNumCols(v, 1); sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC); } delete_from_cleanup: sqlite3AuthContextPop(&sContext); sqlite3SrcListDelete(db, pTabList); sqlite3ExprDelete(db, pWhere); sqlite3DbFree(db, aToOpen); return; }
/* ** strftime( FORMAT, TIMESTRING, MOD, MOD, ...) ** ** Return a string described by FORMAT. Conversions as follows: ** ** %d day of month ** %f ** fractional seconds SS.SSS ** %H hour 00-24 ** %j day of year 000-366 ** %J ** julian day number ** %m month 01-12 ** %M minute 00-59 ** %s seconds since 1970-01-01 ** %S seconds 00-59 ** %w day of week 0-6 sunday==0 ** %W week of year 00-53 ** %Y year 0000-9999 ** %% % */ static void strftimeFunc( sqlite3_context *context, int argc, sqlite3_value **argv ){ DateTime x; u64 n; size_t i,j; char *z; sqlite3 *db; const char *zFmt; char zBuf[100]; if( argc==0 ) return; zFmt = (const char*)sqlite3_value_text(argv[0]); if( zFmt==0 || isDate(context, argc-1, argv+1, &x) ) return; db = sqlite3_context_db_handle(context); for(i=0, n=1; zFmt[i]; i++, n++){ if( zFmt[i]=='%' ){ switch( zFmt[i+1] ){ case 'd': case 'H': case 'm': case 'M': case 'S': case 'W': n++; /* fall thru */ case 'w': case '%': break; case 'f': n += 8; break; case 'j': n += 3; break; case 'Y': n += 8; break; case 's': case 'J': n += 50; break; default: return; /* ERROR. return a NULL */ } i++; } } testcase( n==sizeof(zBuf)-1 ); testcase( n==sizeof(zBuf) ); testcase( n==(u64)db->aLimit[SQLITE_LIMIT_LENGTH]+1 ); testcase( n==(u64)db->aLimit[SQLITE_LIMIT_LENGTH] ); if( n<sizeof(zBuf) ){ z = zBuf; }else if( n>(u64)db->aLimit[SQLITE_LIMIT_LENGTH] ){ sqlite3_result_error_toobig(context); return; }else{ z = sqlite3DbMallocRawNN(db, (int)n); if( z==0 ){ sqlite3_result_error_nomem(context); return; } } computeJD(&x); computeYMD_HMS(&x); for(i=j=0; zFmt[i]; i++){ if( zFmt[i]!='%' ){ z[j++] = zFmt[i]; }else{ i++; switch( zFmt[i] ){ case 'd': sqlite3_snprintf(3, &z[j],"%02d",x.D); j+=2; break; case 'f': { double s = x.s; if( s>59.999 ) s = 59.999; sqlite3_snprintf(7, &z[j],"%06.3f", s); j += sqlite3Strlen30(&z[j]); break; } case 'H': sqlite3_snprintf(3, &z[j],"%02d",x.h); j+=2; break; case 'W': /* Fall thru */ case 'j': { int nDay; /* Number of days since 1st day of year */ DateTime y = x; y.validJD = 0; y.M = 1; y.D = 1; computeJD(&y); nDay = (int)((x.iJD-y.iJD+43200000)/86400000); if( zFmt[i]=='W' ){ int wd; /* 0=Monday, 1=Tuesday, ... 6=Sunday */ wd = (int)(((x.iJD+43200000)/86400000)%7); sqlite3_snprintf(3, &z[j],"%02d",(nDay+7-wd)/7); j += 2; }else{ sqlite3_snprintf(4, &z[j],"%03d",nDay+1); j += 3; } break; } case 'J': { sqlite3_snprintf(20, &z[j],"%.16g",x.iJD/86400000.0); j+=sqlite3Strlen30(&z[j]); break; } case 'm': sqlite3_snprintf(3, &z[j],"%02d",x.M); j+=2; break; case 'M': sqlite3_snprintf(3, &z[j],"%02d",x.m); j+=2; break; case 's': { sqlite3_snprintf(30,&z[j],"%lld", (i64)(x.iJD/1000 - 21086676*(i64)10000)); j += sqlite3Strlen30(&z[j]); break; } case 'S': sqlite3_snprintf(3,&z[j],"%02d",(int)x.s); j+=2; break; case 'w': { z[j++] = (char)(((x.iJD+129600000)/86400000) % 7) + '0'; break; } case 'Y': { sqlite3_snprintf(5,&z[j],"%04d",x.Y); j+=sqlite3Strlen30(&z[j]); break; } default: z[j++] = '%'; break; } } } z[j] = 0; sqlite3_result_text(context, z, -1, z==zBuf ? SQLITE_TRANSIENT : SQLITE_DYNAMIC); }
/* ** An SQL user-function registered to do the work of an ATTACH statement. The ** three arguments to the function come directly from an attach statement: ** ** ATTACH DATABASE x AS y KEY z ** ** SELECT sqlite_attach(x, y, z) ** ** If the optional "KEY z" syntax is omitted, an SQL NULL is passed as the ** third argument. */ static void attachFunc( sqlite3_context *context, int NotUsed, sqlite3_value **argv ){ int i; int rc = 0; sqlite3 *db = sqlite3_context_db_handle(context); const char *zName; const char *zFile; char *zPath = 0; char *zErr = 0; unsigned int flags; Db *aNew; char *zErrDyn = 0; sqlite3_vfs *pVfs; UNUSED_PARAMETER(NotUsed); zFile = (const char *)sqlite3_value_text(argv[0]); zName = (const char *)sqlite3_value_text(argv[1]); if( zFile==0 ) zFile = ""; if( zName==0 ) zName = ""; /* Check for the following errors: ** ** * Too many attached databases, ** * Transaction currently open ** * Specified database name already being used. */ if( db->nDb>=db->aLimit[SQLITE_LIMIT_ATTACHED]+2 ){ zErrDyn = sqlite3MPrintf(db, "too many attached databases - max %d", db->aLimit[SQLITE_LIMIT_ATTACHED] ); goto attach_error; } if( !db->autoCommit ){ zErrDyn = sqlite3MPrintf(db, "cannot ATTACH database within transaction"); goto attach_error; } for(i=0; i<db->nDb; i++){ char *z = db->aDb[i].zName; assert( z && zName ); if( sqlite3StrICmp(z, zName)==0 ){ zErrDyn = sqlite3MPrintf(db, "database %s is already in use", zName); goto attach_error; } } /* Allocate the new entry in the db->aDb[] array and initialize the schema ** hash tables. */ if( db->aDb==db->aDbStatic ){ aNew = sqlite3DbMallocRawNN(db, sizeof(db->aDb[0])*3 ); if( aNew==0 ) return; memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2); }else{ aNew = sqlite3DbRealloc(db, db->aDb, sizeof(db->aDb[0])*(db->nDb+1) ); if( aNew==0 ) return; } db->aDb = aNew; aNew = &db->aDb[db->nDb]; memset(aNew, 0, sizeof(*aNew)); /* Open the database file. If the btree is successfully opened, use ** it to obtain the database schema. At this point the schema may ** or may not be initialized. */ flags = db->openFlags; rc = sqlite3ParseUri(db->pVfs->zName, zFile, &flags, &pVfs, &zPath, &zErr); if( rc!=SQLITE_OK ){ if( rc==SQLITE_NOMEM ) sqlite3OomFault(db); sqlite3_result_error(context, zErr, -1); sqlite3_free(zErr); return; } assert( pVfs ); flags |= SQLITE_OPEN_MAIN_DB; rc = sqlite3BtreeOpen(pVfs, zPath, db, &aNew->pBt, 0, flags); sqlite3_free( zPath ); db->nDb++; if( rc==SQLITE_CONSTRAINT ){ rc = SQLITE_ERROR; zErrDyn = sqlite3MPrintf(db, "database is already attached"); }else if( rc==SQLITE_OK ){ Pager *pPager; aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt); if( !aNew->pSchema ){ rc = SQLITE_NOMEM; }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){ zErrDyn = sqlite3MPrintf(db, "attached databases must use the same text encoding as main database"); rc = SQLITE_ERROR; } sqlite3BtreeEnter(aNew->pBt); pPager = sqlite3BtreePager(aNew->pBt); sqlite3PagerLockingMode(pPager, db->dfltLockMode); sqlite3BtreeSecureDelete(aNew->pBt, sqlite3BtreeSecureDelete(db->aDb[0].pBt,-1) ); #ifndef SQLITE_OMIT_PAGER_PRAGMAS sqlite3BtreeSetPagerFlags(aNew->pBt, PAGER_SYNCHRONOUS_FULL | (db->flags & PAGER_FLAGS_MASK)); #endif sqlite3BtreeLeave(aNew->pBt); } aNew->safety_level = 3; aNew->zName = sqlite3DbStrDup(db, zName); if( rc==SQLITE_OK && aNew->zName==0 ){ rc = SQLITE_NOMEM; } #ifdef SQLITE_HAS_CODEC if( rc==SQLITE_OK ){ extern int sqlite3CodecAttach(sqlite3*, int, const void*, int); extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*); int nKey; char *zKey; int t = sqlite3_value_type(argv[2]); switch( t ){ case SQLITE_INTEGER: case SQLITE_FLOAT: zErrDyn = sqlite3DbStrDup(db, "Invalid key value"); rc = SQLITE_ERROR; break; case SQLITE_TEXT: case SQLITE_BLOB: nKey = sqlite3_value_bytes(argv[2]); zKey = (char *)sqlite3_value_blob(argv[2]); rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey); break; case SQLITE_NULL: /* No key specified. Use the key from the main database */ sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey); if( nKey>0 || sqlite3BtreeGetOptimalReserve(db->aDb[0].pBt)>0 ){ rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey); } break; } } #endif /* If the file was opened successfully, read the schema for the new database. ** If this fails, or if opening the file failed, then close the file and ** remove the entry from the db->aDb[] array. i.e. put everything back the way ** we found it. */ if( rc==SQLITE_OK ){ sqlite3BtreeEnterAll(db); rc = sqlite3Init(db, &zErrDyn); sqlite3BtreeLeaveAll(db); } #ifdef SQLITE_USER_AUTHENTICATION if( rc==SQLITE_OK ){ u8 newAuth = 0; rc = sqlite3UserAuthCheckLogin(db, zName, &newAuth); if( newAuth<db->auth.authLevel ){ rc = SQLITE_AUTH_USER; } } #endif if( rc ){ int iDb = db->nDb - 1; assert( iDb>=2 ); if( db->aDb[iDb].pBt ){ sqlite3BtreeClose(db->aDb[iDb].pBt); db->aDb[iDb].pBt = 0; db->aDb[iDb].pSchema = 0; } sqlite3ResetAllSchemasOfConnection(db); db->nDb = iDb; if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){ sqlite3OomFault(db); sqlite3DbFree(db, zErrDyn); zErrDyn = sqlite3MPrintf(db, "out of memory"); }else if( zErrDyn==0 ){ zErrDyn = sqlite3MPrintf(db, "unable to open database: %s", zFile); } goto attach_error; } return; attach_error: /* Return an error if we get here */ if( zErrDyn ){ sqlite3_result_error(context, zErrDyn, -1); sqlite3DbFree(db, zErrDyn); } if( rc ) sqlite3_result_error_code(context, rc); }
/* ** 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; }