diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/expr.c | 70 | ||||
-rw-r--r-- | src/sqliteInt.h | 2 | ||||
-rw-r--r-- | src/where.c | 58 |
3 files changed, 71 insertions, 59 deletions
diff --git a/src/expr.c b/src/expr.c index 1b18828dd..83b1ff56c 100644 --- a/src/expr.c +++ b/src/expr.c @@ -1164,6 +1164,7 @@ Expr *sqlite3ExprFunction( ){ Expr *pNew; sqlite3 *db = pParse->db; + int ii; assert( pToken ); pNew = sqlite3ExprAlloc(db, TK_FUNCTION, pToken, 1); if( pNew==0 ){ @@ -1178,6 +1179,11 @@ Expr *sqlite3ExprFunction( ){ sqlite3ErrorMsg(pParse, "too many arguments on function %T", pToken); } + if( pList && pParse->nErr==0 ){ + for(ii=0; ii<pList->nExpr; ii++){ + ExprSetProperty(pList->a[ii].pExpr, EP_FuncArg); + } + } pNew->x.pList = pList; ExprSetProperty(pNew, EP_HasFunc); assert( ExprUseXList(pNew) ); @@ -4555,6 +4561,59 @@ static int exprCodeInlineFunction( } /* +** Expression Node callback for sqlite3ExprCanReturnSubtype(). +** +** Only a function call is able to return a subtype. So if the node +** is not a function call, return WRC_Prune immediately. +** +** A function call is able to return a subtype if it has the +** SQLITE_RESULT_SUBTYPE property. +** +** Assume that every function is able to pass-through a subtype from +** one of its argument (using sqlite3_result_value()). Most functions +** are not this way, but we don't have a mechanism to distinguish those +** that are from those that are not, so assume they all work this way. +** That means that if one of its arguments is another function and that +** other function is able to return a subtype, then this function is +** able to return a subtype. +*/ +static int exprNodeCanReturnSubtype(Walker *pWalker, Expr *pExpr){ + int n; + FuncDef *pDef; + sqlite3 *db; + if( pExpr->op!=TK_FUNCTION ){ + return WRC_Prune; + } + assert( ExprUseXList(pExpr) ); + db = pWalker->pParse->db; + n = pExpr->x.pList ? pExpr->x.pList->nExpr : 0; + pDef = sqlite3FindFunction(db, pExpr->u.zToken, n, ENC(db), 0); + if( pDef==0 || (pDef->funcFlags & SQLITE_RESULT_SUBTYPE)!=0 ){ + pWalker->eCode = 1; + return WRC_Prune; + } + return WRC_Continue; +} + +/* +** Return TRUE if expression pExpr is able to return a subtype. +** +** A TRUE return does not guarantee that a subtype will be returned. +** It only indicates that a subtype return is possible. False positives +** are acceptable as they only disable an optimization. False negatives, +** on the other hand, can lead to incorrect answers. +*/ +static int sqlite3ExprCanReturnSubtype(Parse *pParse, Expr *pExpr){ + Walker w; + memset(&w, 0, sizeof(w)); + w.pParse = pParse; + w.xExprCallback = exprNodeCanReturnSubtype; + sqlite3WalkExpr(&w, pExpr); + return w.eCode; +} + + +/* ** Check to see if pExpr is one of the indexed expressions on pParse->pIdxEpr. ** If it is, then resolve the expression by reading from the index and ** return the register into which the value has been read. If pExpr is @@ -4586,6 +4645,17 @@ static SQLITE_NOINLINE int sqlite3IndexedExprLookup( continue; } + + /* Functions that might set a subtype should not be replaced by the + ** value taken from an expression index if they are themselves an + ** argument to another scalar function or aggregate. + ** https://sqlite.org/forum/forumpost/68d284c86b082c3e */ + if( ExprHasProperty(pExpr, EP_FuncArg) + && sqlite3ExprCanReturnSubtype(pParse, pExpr) + ){ + continue; + } + v = pParse->pVdbe; assert( v!=0 ); if( p->bMaybeNullRow ){ diff --git a/src/sqliteInt.h b/src/sqliteInt.h index 0e0035ce6..828878670 100644 --- a/src/sqliteInt.h +++ b/src/sqliteInt.h @@ -3104,7 +3104,7 @@ struct Expr { #define EP_IsTrue 0x10000000 /* Always has boolean value of TRUE */ #define EP_IsFalse 0x20000000 /* Always has boolean value of FALSE */ #define EP_FromDDL 0x40000000 /* Originates from sqlite_schema */ - /* 0x80000000 // Available */ +#define EP_FuncArg 0x80000000 /* Is a function() argument */ /* The EP_Propagate mask is a set of properties that automatically propagate ** upwards into parent nodes. diff --git a/src/where.c b/src/where.c index 9aaa082cd..c2fc33824 100644 --- a/src/where.c +++ b/src/where.c @@ -6303,58 +6303,6 @@ static SQLITE_NOINLINE void whereCheckIfBloomFilterIsUseful( } /* -** Expression Node callback for sqlite3ExprCanReturnSubtype(). -** -** Only a function call is able to return a subtype. So if the node -** is not a function call, return WRC_Prune immediately. -** -** A function call is able to return a subtype if it has the -** SQLITE_RESULT_SUBTYPE property. -** -** Assume that every function is able to pass-through a subtype from -** one of its argument (using sqlite3_result_value()). Most functions -** are not this way, but we don't have a mechanism to distinguish those -** that are from those that are not, so assume they all work this way. -** That means that if one of its arguments is another function and that -** other function is able to return a subtype, then this function is -** able to return a subtype. -*/ -static int exprNodeCanReturnSubtype(Walker *pWalker, Expr *pExpr){ - int n; - FuncDef *pDef; - sqlite3 *db; - if( pExpr->op!=TK_FUNCTION ){ - return WRC_Prune; - } - assert( ExprUseXList(pExpr) ); - db = pWalker->pParse->db; - n = pExpr->x.pList ? pExpr->x.pList->nExpr : 0; - pDef = sqlite3FindFunction(db, pExpr->u.zToken, n, ENC(db), 0); - if( pDef==0 || (pDef->funcFlags & SQLITE_RESULT_SUBTYPE)!=0 ){ - pWalker->eCode = 1; - return WRC_Prune; - } - return WRC_Continue; -} - -/* -** Return TRUE if expression pExpr is able to return a subtype. -** -** A TRUE return does not guarantee that a subtype will be returned. -** It only indicates that a subtype return is possible. False positives -** are acceptable as they only disable an optimization. False negatives, -** on the other hand, can lead to incorrect answers. -*/ -static int sqlite3ExprCanReturnSubtype(Parse *pParse, Expr *pExpr){ - Walker w; - memset(&w, 0, sizeof(w)); - w.pParse = pParse; - w.xExprCallback = exprNodeCanReturnSubtype; - sqlite3WalkExpr(&w, pExpr); - return w.eCode; -} - -/* ** The index pIdx is used by a query and contains one or more expressions. ** In other words pIdx is an index on an expression. iIdxCur is the cursor ** number for the index and iDataCur is the cursor number for the corresponding @@ -6387,12 +6335,6 @@ static SQLITE_NOINLINE void whereAddIndexedExpr( continue; } if( sqlite3ExprIsConstant(0,pExpr) ) continue; - if( pExpr->op==TK_FUNCTION && sqlite3ExprCanReturnSubtype(pParse,pExpr) ){ - /* Functions that might set a subtype should not be replaced by the - ** value taken from an expression index since the index omits the - ** subtype. https://sqlite.org/forum/forumpost/68d284c86b082c3e */ - continue; - } p = sqlite3DbMallocRaw(pParse->db, sizeof(IndexedExpr)); if( p==0 ) break; p->pIENext = pParse->pIdxEpr; |