diff options
Diffstat (limited to 'lang/sql/sqlite/src/fkey.c')
| -rw-r--r-- | lang/sql/sqlite/src/fkey.c | 363 |
1 files changed, 266 insertions, 97 deletions
diff --git a/lang/sql/sqlite/src/fkey.c b/lang/sql/sqlite/src/fkey.c index 34fdfda5..46c90a09 100644 --- a/lang/sql/sqlite/src/fkey.c +++ b/lang/sql/sqlite/src/fkey.c @@ -21,8 +21,9 @@ ** -------------------------- ** ** Foreign keys in SQLite come in two flavours: deferred and immediate. -** If an immediate foreign key constraint is violated, SQLITE_CONSTRAINT -** is returned and the current statement transaction rolled back. If a +** If an immediate foreign key constraint is violated, +** SQLITE_CONSTRAINT_FOREIGNKEY is returned and the current +** statement transaction rolled back. If a ** deferred foreign key constraint is violated, no action is taken ** immediately. However if the application attempts to commit the ** transaction before fixing the constraint violation, the attempt fails. @@ -86,7 +87,8 @@ ** Immediate constraints are usually handled similarly. The only difference ** is that the counter used is stored as part of each individual statement ** object (struct Vdbe). If, after the statement has run, its immediate -** constraint counter is greater than zero, it returns SQLITE_CONSTRAINT +** constraint counter is greater than zero, +** it returns SQLITE_CONSTRAINT_FOREIGNKEY ** and the statement transaction is rolled back. An exception is an INSERT ** statement that inserts a single row only (no triggers). In this case, ** instead of using a counter, an exception is thrown immediately if the @@ -142,7 +144,7 @@ ** A foreign key constraint requires that the key columns in the parent ** table are collectively subject to a UNIQUE or PRIMARY KEY constraint. ** Given that pParent is the parent table for foreign key constraint pFKey, -** search the schema a unique index on the parent key columns. +** search the schema for a unique index on the parent key columns. ** ** If successful, zero is returned. If the parent key is an INTEGER PRIMARY ** KEY column, then output variable *ppIdx is set to NULL. Otherwise, *ppIdx @@ -178,7 +180,7 @@ ** into pParse. If an OOM error occurs, non-zero is returned and the ** pParse->db->mallocFailed flag is set. */ -static int locateFkeyIndex( +int sqlite3FkLocateIndex( Parse *pParse, /* Parse context to store any error in */ Table *pParent, /* Parent table of FK constraint pFKey */ FKey *pFKey, /* Foreign key to find index for */ @@ -223,7 +225,7 @@ static int locateFkeyIndex( } for(pIdx=pParent->pIndex; pIdx; pIdx=pIdx->pNext){ - if( pIdx->nColumn==nCol && pIdx->onError!=OE_None ){ + if( pIdx->nKeyCol==nCol && pIdx->onError!=OE_None ){ /* pIdx is a UNIQUE index (or a PRIMARY KEY) and has the right number ** of columns. If each indexed column corresponds to a foreign key ** column of pFKey, then this index is a winner. */ @@ -246,7 +248,7 @@ static int locateFkeyIndex( ** the default collation sequences for each column. */ int i, j; for(i=0; i<nCol; i++){ - int iCol = pIdx->aiColumn[i]; /* Index of column in parent tbl */ + i16 iCol = pIdx->aiColumn[i]; /* Index of column in parent tbl */ char *zDfltColl; /* Def. collation for column */ char *zIdxCol; /* Name of indexed column */ @@ -275,7 +277,9 @@ static int locateFkeyIndex( if( !pIdx ){ if( !pParse->disableTriggers ){ - sqlite3ErrorMsg(pParse, "foreign key mismatch"); + sqlite3ErrorMsg(pParse, + "foreign key mismatch - \"%w\" referencing \"%w\"", + pFKey->pFrom->zName, pFKey->zTo); } sqlite3DbFree(pParse->db, aiCol); return 1; @@ -375,10 +379,9 @@ static void fkLookupParent( int nCol = pFKey->nCol; int regTemp = sqlite3GetTempRange(pParse, nCol); int regRec = sqlite3GetTempReg(pParse); - KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx); sqlite3VdbeAddOp3(v, OP_OpenRead, iCur, pIdx->tnum, iDb); - sqlite3VdbeChangeP4(v, -1, (char*)pKey, P4_KEYINFO_HANDOFF); + sqlite3VdbeSetP4KeyInfo(pParse, pIdx); for(i=0; i<nCol; i++){ sqlite3VdbeAddOp2(v, OP_Copy, aiCol[i]+1+regData, regTemp+i); } @@ -386,13 +389,25 @@ static void fkLookupParent( /* If the parent table is the same as the child table, and we are about ** to increment the constraint-counter (i.e. this is an INSERT operation), ** then check if the row being inserted matches itself. If so, do not - ** increment the constraint-counter. */ + ** increment the constraint-counter. + ** + ** If any of the parent-key values are NULL, then the row cannot match + ** itself. So set JUMPIFNULL to make sure we do the OP_Found if any + ** of the parent-key values are NULL (at this point it is known that + ** none of the child key values are). + */ if( pTab==pFKey->pFrom && nIncr==1 ){ int iJump = sqlite3VdbeCurrentAddr(v) + nCol + 1; for(i=0; i<nCol; i++){ int iChild = aiCol[i]+1+regData; int iParent = pIdx->aiColumn[i]+1+regData; + assert( aiCol[i]!=pTab->iPKey ); + if( pIdx->aiColumn[i]==pTab->iPKey ){ + /* The parent key is a composite key that includes the IPK column */ + iParent = regData; + } sqlite3VdbeAddOp3(v, OP_Ne, iChild, iJump, iParent); + sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL); } sqlite3VdbeAddOp2(v, OP_Goto, 0, iOk); } @@ -406,15 +421,17 @@ static void fkLookupParent( } } - if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){ + if( !pFKey->isDeferred && !(pParse->db->flags & SQLITE_DeferFKs) + && !pParse->pToplevel + && !pParse->isMultiWrite + ){ /* Special case: If this is an INSERT statement that will insert exactly ** one row into the table, raise a constraint immediately instead of ** incrementing a counter. This is necessary as the VM code is being ** generated for will not open a statement transaction. */ assert( nIncr==1 ); - sqlite3HaltConstraint( - pParse, OE_Abort, "foreign key constraint failed", P4_STATIC - ); + sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_FOREIGNKEY, + OE_Abort, 0, P4_STATIC, P5_ConstraintFK); }else{ if( nIncr>0 && pFKey->isDeferred==0 ){ sqlite3ParseToplevel(pParse)->mayAbort = 1; @@ -426,6 +443,62 @@ static void fkLookupParent( sqlite3VdbeAddOp1(v, OP_Close, iCur); } + +/* +** Return an Expr object that refers to a memory register corresponding +** to column iCol of table pTab. +** +** regBase is the first of an array of register that contains the data +** for pTab. regBase itself holds the rowid. regBase+1 holds the first +** column. regBase+2 holds the second column, and so forth. +*/ +static Expr *exprTableRegister( + Parse *pParse, /* Parsing and code generating context */ + Table *pTab, /* The table whose content is at r[regBase]... */ + int regBase, /* Contents of table pTab */ + i16 iCol /* Which column of pTab is desired */ +){ + Expr *pExpr; + Column *pCol; + const char *zColl; + sqlite3 *db = pParse->db; + + pExpr = sqlite3Expr(db, TK_REGISTER, 0); + if( pExpr ){ + if( iCol>=0 && iCol!=pTab->iPKey ){ + pCol = &pTab->aCol[iCol]; + pExpr->iTable = regBase + iCol + 1; + pExpr->affinity = pCol->affinity; + zColl = pCol->zColl; + if( zColl==0 ) zColl = db->pDfltColl->zName; + pExpr = sqlite3ExprAddCollateString(pParse, pExpr, zColl); + }else{ + pExpr->iTable = regBase; + pExpr->affinity = SQLITE_AFF_INTEGER; + } + } + return pExpr; +} + +/* +** Return an Expr object that refers to column iCol of table pTab which +** has cursor iCur. +*/ +static Expr *exprTableColumn( + sqlite3 *db, /* The database connection */ + Table *pTab, /* The table whose column is desired */ + int iCursor, /* The open cursor on the table */ + i16 iCol /* The column that is wanted */ +){ + Expr *pExpr = sqlite3Expr(db, TK_COLUMN, 0); + if( pExpr ){ + pExpr->pTab = pTab; + pExpr->iTable = iCursor; + pExpr->iColumn = iCol; + } + return pExpr; +} + /* ** This function is called to generate code executed when a row is deleted ** from the parent table of foreign key constraint pFKey and, if pFKey is @@ -441,13 +514,13 @@ static void fkLookupParent( ** -------------------------------------------------------------------------- ** DELETE immediate Increment the "immediate constraint counter". ** Or, if the ON (UPDATE|DELETE) action is RESTRICT, -** throw a "foreign key constraint failed" exception. +** throw a "FOREIGN KEY constraint failed" exception. ** ** INSERT immediate Decrement the "immediate constraint counter". ** ** DELETE deferred Increment the "deferred constraint counter". ** Or, if the ON (UPDATE|DELETE) action is RESTRICT, -** throw a "foreign key constraint failed" exception. +** throw a "FOREIGN KEY constraint failed" exception. ** ** INSERT deferred Decrement the "deferred constraint counter". ** @@ -456,12 +529,12 @@ static void fkLookupParent( */ static void fkScanChildren( Parse *pParse, /* Parse context */ - SrcList *pSrc, /* SrcList containing the table to scan */ - Table *pTab, - Index *pIdx, /* Foreign key index */ - FKey *pFKey, /* Foreign key relationship */ + SrcList *pSrc, /* The child table to be scanned */ + Table *pTab, /* The parent table */ + Index *pIdx, /* Index on parent covering the foreign key */ + FKey *pFKey, /* The foreign key linking pSrc to pTab */ int *aiCol, /* Map from pIdx cols to child table cols */ - int regData, /* Referenced table data starts here */ + int regData, /* Parent row data starts here */ int nIncr /* Amount to increment deferred counter by */ ){ sqlite3 *db = pParse->db; /* Database handle */ @@ -472,7 +545,10 @@ static void fkScanChildren( int iFkIfZero = 0; /* Address of OP_FkIfZero */ Vdbe *v = sqlite3GetVdbe(pParse); - assert( !pIdx || pIdx->pTable==pTab ); + assert( pIdx==0 || pIdx->pTable==pTab ); + assert( pIdx==0 || pIdx->nKeyCol==pFKey->nCol ); + assert( pIdx!=0 || pFKey->nCol==1 ); + assert( pIdx!=0 || HasRowid(pTab) ); if( nIncr<0 ){ iFkIfZero = sqlite3VdbeAddOp2(v, OP_FkIfZero, pFKey->isDeferred, 0); @@ -490,26 +566,11 @@ static void fkScanChildren( Expr *pLeft; /* Value from parent table row */ Expr *pRight; /* Column ref to child table */ Expr *pEq; /* Expression (pLeft = pRight) */ - int iCol; /* Index of column in child table */ + i16 iCol; /* Index of column in child table */ const char *zCol; /* Name of column in child table */ - pLeft = sqlite3Expr(db, TK_REGISTER, 0); - if( pLeft ){ - /* Set the collation sequence and affinity of the LHS of each TK_EQ - ** expression to the parent key column defaults. */ - if( pIdx ){ - Column *pCol; - iCol = pIdx->aiColumn[i]; - pCol = &pTab->aCol[iCol]; - if( pTab->iPKey==iCol ) iCol = -1; - pLeft->iTable = regData+iCol+1; - pLeft->affinity = pCol->affinity; - pLeft->pColl = sqlite3LocateCollSeq(pParse, pCol->zColl); - }else{ - pLeft->iTable = regData; - pLeft->affinity = SQLITE_AFF_INTEGER; - } - } + iCol = pIdx ? pIdx->aiColumn[i] : -1; + pLeft = exprTableRegister(pParse, pTab, regData, iCol); iCol = aiCol ? aiCol[i] : pFKey->aCol[0].iFrom; assert( iCol>=0 ); zCol = pFKey->pFrom->aCol[iCol].zName; @@ -518,24 +579,39 @@ static void fkScanChildren( pWhere = sqlite3ExprAnd(db, pWhere, pEq); } - /* If the child table is the same as the parent table, and this scan - ** is taking place as part of a DELETE operation (operation D.2), omit the - ** row being deleted from the scan by adding ($rowid != rowid) to the WHERE - ** clause, where $rowid is the rowid of the row being deleted. */ + /* If the child table is the same as the parent table, then add terms + ** to the WHERE clause that prevent this entry from being scanned. + ** The added WHERE clause terms are like this: + ** + ** $current_rowid!=rowid + ** NOT( $current_a==a AND $current_b==b AND ... ) + ** + ** The first form is used for rowid tables. The second form is used + ** for WITHOUT ROWID tables. In the second form, the primary key is + ** (a,b,...) + */ if( pTab==pFKey->pFrom && nIncr>0 ){ - Expr *pEq; /* Expression (pLeft = pRight) */ + Expr *pNe; /* Expression (pLeft != pRight) */ Expr *pLeft; /* Value from parent table row */ Expr *pRight; /* Column ref to child table */ - pLeft = sqlite3Expr(db, TK_REGISTER, 0); - pRight = sqlite3Expr(db, TK_COLUMN, 0); - if( pLeft && pRight ){ - pLeft->iTable = regData; - pLeft->affinity = SQLITE_AFF_INTEGER; - pRight->iTable = pSrc->a[0].iCursor; - pRight->iColumn = -1; + if( HasRowid(pTab) ){ + pLeft = exprTableRegister(pParse, pTab, regData, -1); + pRight = exprTableColumn(db, pTab, pSrc->a[0].iCursor, -1); + pNe = sqlite3PExpr(pParse, TK_NE, pLeft, pRight, 0); + }else{ + Expr *pEq, *pAll = 0; + Index *pPk = sqlite3PrimaryKeyIndex(pTab); + assert( pIdx!=0 ); + for(i=0; i<pPk->nKeyCol; i++){ + i16 iCol = pIdx->aiColumn[i]; + pLeft = exprTableRegister(pParse, pTab, regData, iCol); + pRight = exprTableColumn(db, pTab, pSrc->a[0].iCursor, iCol); + pEq = sqlite3PExpr(pParse, TK_EQ, pLeft, pRight, 0); + pAll = sqlite3ExprAnd(db, pAll, pEq); + } + pNe = sqlite3PExpr(pParse, TK_NOT, pAll, 0, 0); } - pEq = sqlite3PExpr(pParse, TK_NE, pLeft, pRight, 0); - pWhere = sqlite3ExprAnd(db, pWhere, pEq); + pWhere = sqlite3ExprAnd(db, pWhere, pNe); } /* Resolve the references in the WHERE clause. */ @@ -548,7 +624,7 @@ static void fkScanChildren( ** clause. If the constraint is not deferred, throw an exception for ** each row found. Otherwise, for deferred constraints, increment the ** deferred constraint counter by nIncr for each row selected. */ - pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0, 0); + pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0, 0, 0, 0); if( nIncr>0 && pFKey->isDeferred==0 ){ sqlite3ParseToplevel(pParse)->mayAbort = 1; } @@ -565,8 +641,8 @@ static void fkScanChildren( } /* -** This function returns a pointer to the head of a linked list of FK -** constraints for which table pTab is the parent table. For example, +** This function returns a linked list of FKey objects (connected by +** FKey.pNextTo) holding all children of table pTab. For example, ** given the following schema: ** ** CREATE TABLE t1(a PRIMARY KEY); @@ -634,7 +710,7 @@ void sqlite3FkDropTable(Parse *pParse, SrcList *pName, Table *pTab){ ** when this statement is run. */ FKey *p; for(p=pTab->pFKey; p; p=p->pNextFrom){ - if( p->isDeferred ) break; + if( p->isDeferred || (db->flags & SQLITE_DeferFKs) ) break; } if( !p ) return; iSkip = sqlite3VdbeMakeLabel(v); @@ -648,11 +724,17 @@ void sqlite3FkDropTable(Parse *pParse, SrcList *pName, Table *pTab){ /* If the DELETE has generated immediate foreign key constraint ** violations, halt the VDBE and return an error at this point, before ** any modifications to the schema are made. This is because statement - ** transactions are not able to rollback schema changes. */ - sqlite3VdbeAddOp2(v, OP_FkIfZero, 0, sqlite3VdbeCurrentAddr(v)+2); - sqlite3HaltConstraint( - pParse, OE_Abort, "foreign key constraint failed", P4_STATIC - ); + ** transactions are not able to rollback schema changes. + ** + ** If the SQLITE_DeferFKs flag is set, then this is not required, as + ** the statement transaction will not be rolled back even if FK + ** constraints are violated. + */ + if( (db->flags & SQLITE_DeferFKs)==0 ){ + sqlite3VdbeAddOp2(v, OP_FkIfZero, 0, sqlite3VdbeCurrentAddr(v)+2); + sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_FOREIGNKEY, + OE_Abort, 0, P4_STATIC, P5_ConstraintFK); + } if( iSkip ){ sqlite3VdbeResolveLabel(v, iSkip); @@ -660,6 +742,70 @@ void sqlite3FkDropTable(Parse *pParse, SrcList *pName, Table *pTab){ } } + +/* +** The second argument points to an FKey object representing a foreign key +** for which pTab is the child table. An UPDATE statement against pTab +** is currently being processed. For each column of the table that is +** actually updated, the corresponding element in the aChange[] array +** is zero or greater (if a column is unmodified the corresponding element +** is set to -1). If the rowid column is modified by the UPDATE statement +** the bChngRowid argument is non-zero. +** +** This function returns true if any of the columns that are part of the +** child key for FK constraint *p are modified. +*/ +static int fkChildIsModified( + Table *pTab, /* Table being updated */ + FKey *p, /* Foreign key for which pTab is the child */ + int *aChange, /* Array indicating modified columns */ + int bChngRowid /* True if rowid is modified by this update */ +){ + int i; + for(i=0; i<p->nCol; i++){ + int iChildKey = p->aCol[i].iFrom; + if( aChange[iChildKey]>=0 ) return 1; + if( iChildKey==pTab->iPKey && bChngRowid ) return 1; + } + return 0; +} + +/* +** The second argument points to an FKey object representing a foreign key +** for which pTab is the parent table. An UPDATE statement against pTab +** is currently being processed. For each column of the table that is +** actually updated, the corresponding element in the aChange[] array +** is zero or greater (if a column is unmodified the corresponding element +** is set to -1). If the rowid column is modified by the UPDATE statement +** the bChngRowid argument is non-zero. +** +** This function returns true if any of the columns that are part of the +** parent key for FK constraint *p are modified. +*/ +static int fkParentIsModified( + Table *pTab, + FKey *p, + int *aChange, + int bChngRowid +){ + int i; + for(i=0; i<p->nCol; i++){ + char *zKey = p->aCol[i].zCol; + int iKey; + for(iKey=0; iKey<pTab->nCol; iKey++){ + if( aChange[iKey]>=0 || (iKey==pTab->iPKey && bChngRowid) ){ + Column *pCol = &pTab->aCol[iKey]; + if( zKey ){ + if( 0==sqlite3StrICmp(pCol->zName, zKey) ) return 1; + }else if( pCol->colFlags & COLFLAG_PRIMKEY ){ + return 1; + } + } + } + } + return 0; +} + /* ** This function is called when inserting, deleting or updating a row of ** table pTab to generate VDBE code to perform foreign key constraint @@ -684,7 +830,9 @@ void sqlite3FkCheck( Parse *pParse, /* Parse context */ Table *pTab, /* Row is being deleted from this table */ int regOld, /* Previous row data is stored here */ - int regNew /* New row data is stored here */ + int regNew, /* New row data is stored here */ + int *aChange, /* Array indicating UPDATEd columns (or 0) */ + int bChngRowid /* True if rowid is UPDATEd */ ){ sqlite3 *db = pParse->db; /* Database handle */ FKey *pFKey; /* Used to iterate through FKs */ @@ -712,6 +860,13 @@ void sqlite3FkCheck( int i; int isIgnore = 0; + if( aChange + && sqlite3_stricmp(pTab->zName, pFKey->zTo)!=0 + && fkChildIsModified(pTab, pFKey, aChange, bChngRowid)==0 + ){ + continue; + } + /* Find the parent table of this foreign key. Also find a unique index ** on the parent key columns in the parent table. If either of these ** schema items cannot be located, set an error in pParse and return @@ -721,8 +876,25 @@ void sqlite3FkCheck( }else{ pTo = sqlite3LocateTable(pParse, 0, pFKey->zTo, zDb); } - if( !pTo || locateFkeyIndex(pParse, pTo, pFKey, &pIdx, &aiFree) ){ + if( !pTo || sqlite3FkLocateIndex(pParse, pTo, pFKey, &pIdx, &aiFree) ){ + assert( isIgnoreErrors==0 || (regOld!=0 && regNew==0) ); if( !isIgnoreErrors || db->mallocFailed ) return; + if( pTo==0 ){ + /* If isIgnoreErrors is true, then a table is being dropped. In this + ** case SQLite runs a "DELETE FROM xxx" on the table being dropped + ** before actually dropping it in order to check FK constraints. + ** If the parent table of an FK constraint on the current table is + ** missing, behave as if it is empty. i.e. decrement the relevant + ** FK counter for each row of the current table with non-NULL keys. + */ + Vdbe *v = sqlite3GetVdbe(pParse); + int iJump = sqlite3VdbeCurrentAddr(v) + pFKey->nCol + 1; + for(i=0; i<pFKey->nCol; i++){ + int iReg = pFKey->aCol[i].iFrom + regOld + 1; + sqlite3VdbeAddOp2(v, OP_IsNull, iReg, iJump); + } + sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, -1); + } continue; } assert( pFKey->nCol==1 || (aiFree && pIdx) ); @@ -771,28 +943,34 @@ void sqlite3FkCheck( sqlite3DbFree(db, aiFree); } - /* Loop through all the foreign key constraints that refer to this table */ + /* Loop through all the foreign key constraints that refer to this table. + ** (the "child" constraints) */ for(pFKey = sqlite3FkReferences(pTab); pFKey; pFKey=pFKey->pNextTo){ Index *pIdx = 0; /* Foreign key index for pFKey */ SrcList *pSrc; int *aiCol = 0; - if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){ + if( aChange && fkParentIsModified(pTab, pFKey, aChange, bChngRowid)==0 ){ + continue; + } + + if( !pFKey->isDeferred && !(db->flags & SQLITE_DeferFKs) + && !pParse->pToplevel && !pParse->isMultiWrite + ){ assert( regOld==0 && regNew!=0 ); /* Inserting a single row into a parent table cannot cause an immediate ** foreign key violation. So do nothing in this case. */ continue; } - if( locateFkeyIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ){ + if( sqlite3FkLocateIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ){ if( !isIgnoreErrors || db->mallocFailed ) return; continue; } assert( aiCol || pFKey->nCol==1 ); - /* Create a SrcList structure containing a single table (the table - ** the foreign key that refers to this table is attached to). This - ** is required for the sqlite3WhereXXX() interface. */ + /* Create a SrcList structure containing the child table. We need the + ** child table as a SrcList for sqlite3WhereBegin() */ pSrc = sqlite3SrcListAppend(db, 0, 0, 0); if( pSrc ){ struct SrcList_item *pItem = pSrc->a; @@ -839,15 +1017,16 @@ u32 sqlite3FkOldmask( } for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){ Index *pIdx = 0; - locateFkeyIndex(pParse, pTab, p, &pIdx, 0); + sqlite3FkLocateIndex(pParse, pTab, p, &pIdx, 0); if( pIdx ){ - for(i=0; i<pIdx->nColumn; i++) mask |= COLUMN_MASK(pIdx->aiColumn[i]); + for(i=0; i<pIdx->nKeyCol; i++) mask |= COLUMN_MASK(pIdx->aiColumn[i]); } } } return mask; } + /* ** This function is called before generating code to update or delete a ** row contained in table pTab. If the operation is a DELETE, then @@ -877,31 +1056,16 @@ int sqlite3FkRequired( }else{ /* This is an UPDATE. Foreign key processing is only required if the ** operation modifies one or more child or parent key columns. */ - int i; FKey *p; /* Check if any child key columns are being modified. */ for(p=pTab->pFKey; p; p=p->pNextFrom){ - for(i=0; i<p->nCol; i++){ - int iChildKey = p->aCol[i].iFrom; - if( aChange[iChildKey]>=0 ) return 1; - if( iChildKey==pTab->iPKey && chngRowid ) return 1; - } + if( fkChildIsModified(pTab, p, aChange, chngRowid) ) return 1; } /* Check if any parent key columns are being modified. */ for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){ - for(i=0; i<p->nCol; i++){ - char *zKey = p->aCol[i].zCol; - int iKey; - for(iKey=0; iKey<pTab->nCol; iKey++){ - Column *pCol = &pTab->aCol[iKey]; - if( (zKey ? !sqlite3StrICmp(pCol->zName, zKey) : pCol->isPrimKey) ){ - if( aChange[iKey]>=0 ) return 1; - if( iKey==pTab->iPKey && chngRowid ) return 1; - } - } - } + if( fkParentIsModified(pTab, p, aChange, chngRowid) ) return 1; } } } @@ -964,7 +1128,7 @@ static Trigger *fkActionTrigger( int i; /* Iterator variable */ Expr *pWhen = 0; /* WHEN clause for the trigger */ - if( locateFkeyIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ) return 0; + if( sqlite3FkLocateIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ) return 0; assert( aiCol || pFKey->nCol==1 ); for(i=0; i<pFKey->nCol; i++){ @@ -1047,7 +1211,7 @@ static Trigger *fkActionTrigger( tFrom.z = zFrom; tFrom.n = nFrom; - pRaise = sqlite3Expr(db, TK_RAISE, "foreign key constraint failed"); + pRaise = sqlite3Expr(db, TK_RAISE, "FOREIGN KEY constraint failed"); if( pRaise ){ pRaise->affinity = OE_Abort; } @@ -1095,6 +1259,7 @@ static Trigger *fkActionTrigger( fkTriggerDelete(db, pTrigger); return 0; } + assert( pStep!=0 ); switch( action ){ case OE_Restrict: @@ -1126,7 +1291,9 @@ void sqlite3FkActions( Parse *pParse, /* Parse context */ Table *pTab, /* Table being updated or deleted from */ ExprList *pChanges, /* Change-list for UPDATE, NULL for DELETE */ - int regOld /* Address of array containing old row */ + int regOld, /* Address of array containing old row */ + int *aChange, /* Array indicating UPDATEd columns (or 0) */ + int bChngRowid /* True if rowid is UPDATEd */ ){ /* If foreign-key support is enabled, iterate through all FKs that ** refer to table pTab. If there is an action associated with the FK @@ -1135,9 +1302,11 @@ void sqlite3FkActions( if( pParse->db->flags&SQLITE_ForeignKeys ){ FKey *pFKey; /* Iterator variable */ for(pFKey = sqlite3FkReferences(pTab); pFKey; pFKey=pFKey->pNextTo){ - Trigger *pAction = fkActionTrigger(pParse, pTab, pFKey, pChanges); - if( pAction ){ - sqlite3CodeRowTriggerDirect(pParse, pAction, pTab, regOld, OE_Abort, 0); + if( aChange==0 || fkParentIsModified(pTab, pFKey, aChange, bChngRowid) ){ + Trigger *pAct = fkActionTrigger(pParse, pTab, pFKey, pChanges); + if( pAct ){ + sqlite3CodeRowTriggerDirect(pParse, pAct, pTab, regOld, OE_Abort, 0); + } } } } |