Files
sqlite/src/resolve.c
T
drh 3c5a810646 If a term of an ORDER BY or GROUP BY contains an aggregate function or column,
then it is not an alias that needs to be resolved, so don't try to.  This fixes
a harmless assertion found by dbsqlfuzz.  This yet another problem that
orginated at check-in [6e6b3729e0549de0].

FossilOrigin-Name: d4ec2a5d2297cd9ead0a8768dcf003ea76c74d8d68d88c40f62363f484a4a4d3
2024-02-11 20:53:14 +00:00

2210 lines
79 KiB
C

/*
** 2008 August 18
**
** 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 routines used for walking the parser tree and
** resolve all identifiers by associating them with a particular
** table and column.
*/
#include "sqliteInt.h"
/*
** Magic table number to mean the EXCLUDED table in an UPSERT statement.
*/
#define EXCLUDED_TABLE_NUMBER 2
/*
** Walk the expression tree pExpr and increase the aggregate function
** depth (the Expr.op2 field) by N on every TK_AGG_FUNCTION node.
** This needs to occur when copying a TK_AGG_FUNCTION node from an
** outer query into an inner subquery.
**
** incrAggFunctionDepth(pExpr,n) is the main routine. incrAggDepth(..)
** is a helper function - a callback for the tree walker.
**
** See also the sqlite3WindowExtraAggFuncDepth() routine in window.c
*/
static int incrAggDepth(Walker *pWalker, Expr *pExpr){
if( pExpr->op==TK_AGG_FUNCTION ) pExpr->op2 += pWalker->u.n;
return WRC_Continue;
}
static void incrAggFunctionDepth(Expr *pExpr, int N){
if( N>0 ){
Walker w;
memset(&w, 0, sizeof(w));
w.xExprCallback = incrAggDepth;
w.u.n = N;
sqlite3WalkExpr(&w, pExpr);
}
}
/*
** Turn the pExpr expression into an alias for the iCol-th column of the
** result set in pEList.
**
** If the reference is followed by a COLLATE operator, then make sure
** the COLLATE operator is preserved. For example:
**
** SELECT a+b, c+d FROM t1 ORDER BY 1 COLLATE nocase;
**
** Should be transformed into:
**
** SELECT a+b, c+d FROM t1 ORDER BY (a+b) COLLATE nocase;
**
** The nSubquery parameter specifies how many levels of subquery the
** alias is removed from the original expression. The usual value is
** zero but it might be more if the alias is contained within a subquery
** of the original expression. The Expr.op2 field of TK_AGG_FUNCTION
** structures must be increased by the nSubquery amount.
*/
static void resolveAlias(
Parse *pParse, /* Parsing context */
ExprList *pEList, /* A result set */
int iCol, /* A column in the result set. 0..pEList->nExpr-1 */
Expr *pExpr, /* Transform this into an alias to the result set */
int nSubquery /* Number of subqueries that the label is moving */
){
Expr *pOrig; /* The iCol-th column of the result set */
Expr *pDup; /* Copy of pOrig */
sqlite3 *db; /* The database connection */
assert( iCol>=0 && iCol<pEList->nExpr );
pOrig = pEList->a[iCol].pExpr;
assert( pOrig!=0 );
assert( !ExprHasProperty(pExpr, EP_Reduced|EP_TokenOnly) );
if( pExpr->pAggInfo ) return;
db = pParse->db;
pDup = sqlite3ExprDup(db, pOrig, 0);
if( db->mallocFailed ){
sqlite3ExprDelete(db, pDup);
pDup = 0;
}else{
Expr temp;
incrAggFunctionDepth(pDup, nSubquery);
if( pExpr->op==TK_COLLATE ){
assert( !ExprHasProperty(pExpr, EP_IntValue) );
pDup = sqlite3ExprAddCollateString(pParse, pDup, pExpr->u.zToken);
}
memcpy(&temp, pDup, sizeof(Expr));
memcpy(pDup, pExpr, sizeof(Expr));
memcpy(pExpr, &temp, sizeof(Expr));
if( ExprHasProperty(pExpr, EP_WinFunc) ){
if( ALWAYS(pExpr->y.pWin!=0) ){
pExpr->y.pWin->pOwner = pExpr;
}
}
sqlite3ExprDeferredDelete(pParse, pDup);
}
}
/*
** Subqueries store the original database, table and column names for their
** result sets in ExprList.a[].zSpan, in the form "DATABASE.TABLE.COLUMN",
** and mark the expression-list item by setting ExprList.a[].fg.eEName
** to ENAME_TAB.
**
** Check to see if the zSpan/eEName of the expression-list item passed to this
** routine matches the zDb, zTab, and zCol. If any of zDb, zTab, and zCol are
** NULL then those fields will match anything. Return true if there is a match,
** or false otherwise.
**
** SF_NestedFrom subqueries also store an entry for the implicit rowid (or
** _rowid_, or oid) column by setting ExprList.a[].fg.eEName to ENAME_ROWID,
** and setting zSpan to "DATABASE.TABLE.<rowid-alias>". This type of pItem
** argument matches if zCol is a rowid alias. If it is not NULL, (*pbRowid)
** is set to 1 if there is this kind of match.
*/
int sqlite3MatchEName(
const struct ExprList_item *pItem,
const char *zCol,
const char *zTab,
const char *zDb,
int *pbRowid
){
int n;
const char *zSpan;
int eEName = pItem->fg.eEName;
if( eEName!=ENAME_TAB && (eEName!=ENAME_ROWID || NEVER(pbRowid==0)) ){
return 0;
}
assert( pbRowid==0 || *pbRowid==0 );
zSpan = pItem->zEName;
for(n=0; ALWAYS(zSpan[n]) && zSpan[n]!='.'; n++){}
if( zDb && (sqlite3StrNICmp(zSpan, zDb, n)!=0 || zDb[n]!=0) ){
return 0;
}
zSpan += n+1;
for(n=0; ALWAYS(zSpan[n]) && zSpan[n]!='.'; n++){}
if( zTab && (sqlite3StrNICmp(zSpan, zTab, n)!=0 || zTab[n]!=0) ){
return 0;
}
zSpan += n+1;
if( zCol ){
if( eEName==ENAME_TAB && sqlite3StrICmp(zSpan, zCol)!=0 ) return 0;
if( eEName==ENAME_ROWID && sqlite3IsRowid(zCol)==0 ) return 0;
}
if( eEName==ENAME_ROWID ) *pbRowid = 1;
return 1;
}
/*
** Return TRUE if the double-quoted string mis-feature should be supported.
*/
static int areDoubleQuotedStringsEnabled(sqlite3 *db, NameContext *pTopNC){
if( db->init.busy ) return 1; /* Always support for legacy schemas */
if( pTopNC->ncFlags & NC_IsDDL ){
/* Currently parsing a DDL statement */
if( sqlite3WritableSchema(db) && (db->flags & SQLITE_DqsDML)!=0 ){
return 1;
}
return (db->flags & SQLITE_DqsDDL)!=0;
}else{
/* Currently parsing a DML statement */
return (db->flags & SQLITE_DqsDML)!=0;
}
}
/*
** The argument is guaranteed to be a non-NULL Expr node of type TK_COLUMN.
** return the appropriate colUsed mask.
*/
Bitmask sqlite3ExprColUsed(Expr *pExpr){
int n;
Table *pExTab;
n = pExpr->iColumn;
assert( ExprUseYTab(pExpr) );
pExTab = pExpr->y.pTab;
assert( pExTab!=0 );
assert( n < pExTab->nCol );
if( (pExTab->tabFlags & TF_HasGenerated)!=0
&& (pExTab->aCol[n].colFlags & COLFLAG_GENERATED)!=0
){
testcase( pExTab->nCol==BMS-1 );
testcase( pExTab->nCol==BMS );
return pExTab->nCol>=BMS ? ALLBITS : MASKBIT(pExTab->nCol)-1;
}else{
testcase( n==BMS-1 );
testcase( n==BMS );
if( n>=BMS ) n = BMS-1;
return ((Bitmask)1)<<n;
}
}
/*
** Create a new expression term for the column specified by pMatch and
** iColumn. Append this new expression term to the FULL JOIN Match set
** in *ppList. Create a new *ppList if this is the first term in the
** set.
*/
static void extendFJMatch(
Parse *pParse, /* Parsing context */
ExprList **ppList, /* ExprList to extend */
SrcItem *pMatch, /* Source table containing the column */
i16 iColumn /* The column number */
){
Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLUMN, 0, 0);
if( pNew ){
pNew->iTable = pMatch->iCursor;
pNew->iColumn = iColumn;
pNew->y.pTab = pMatch->pTab;
assert( (pMatch->fg.jointype & (JT_LEFT|JT_LTORJ))!=0 );
ExprSetProperty(pNew, EP_CanBeNull);
*ppList = sqlite3ExprListAppend(pParse, *ppList, pNew);
}
}
/*
** Return TRUE (non-zero) if zTab is a valid name for the schema table pTab.
*/
static SQLITE_NOINLINE int isValidSchemaTableName(
const char *zTab, /* Name as it appears in the SQL */
Table *pTab, /* The schema table we are trying to match */
Schema *pSchema /* non-NULL if a database qualifier is present */
){
const char *zLegacy;
assert( pTab!=0 );
assert( pTab->tnum==1 );
if( sqlite3StrNICmp(zTab, "sqlite_", 7)!=0 ) return 0;
zLegacy = pTab->zName;
if( strcmp(zLegacy+7, &LEGACY_TEMP_SCHEMA_TABLE[7])==0 ){
if( sqlite3StrICmp(zTab+7, &PREFERRED_TEMP_SCHEMA_TABLE[7])==0 ){
return 1;
}
if( pSchema==0 ) return 0;
if( sqlite3StrICmp(zTab+7, &LEGACY_SCHEMA_TABLE[7])==0 ) return 1;
if( sqlite3StrICmp(zTab+7, &PREFERRED_SCHEMA_TABLE[7])==0 ) return 1;
}else{
if( sqlite3StrICmp(zTab+7, &PREFERRED_SCHEMA_TABLE[7])==0 ) return 1;
}
return 0;
}
/*
** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up
** that name in the set of source tables in pSrcList and make the pExpr
** expression node refer back to that source column. The following changes
** are made to pExpr:
**
** pExpr->iDb Set the index in db->aDb[] of the database X
** (even if X is implied).
** pExpr->iTable Set to the cursor number for the table obtained
** from pSrcList.
** pExpr->y.pTab Points to the Table structure of X.Y (even if
** X and/or Y are implied.)
** pExpr->iColumn Set to the column number within the table.
** pExpr->op Set to TK_COLUMN.
** pExpr->pLeft Any expression this points to is deleted
** pExpr->pRight Any expression this points to is deleted.
**
** The zDb variable is the name of the database (the "X"). This value may be
** NULL meaning that name is of the form Y.Z or Z. Any available database
** can be used. The zTable variable is the name of the table (the "Y"). This
** value can be NULL if zDb is also NULL. If zTable is NULL it
** means that the form of the name is Z and that columns from any table
** can be used.
**
** If the name cannot be resolved unambiguously, leave an error message
** in pParse and return WRC_Abort. Return WRC_Prune on success.
*/
static int lookupName(
Parse *pParse, /* The parsing context */
const char *zDb, /* Name of the database containing table, or NULL */
const char *zTab, /* Name of table containing column, or NULL */
const Expr *pRight, /* Name of the column. */
NameContext *pNC, /* The name context used to resolve the name */
Expr *pExpr /* Make this EXPR node point to the selected column */
){
int i, j; /* Loop counters */
int cnt = 0; /* Number of matching column names */
int cntTab = 0; /* Number of potential "rowid" matches */
int nSubquery = 0; /* How many levels of subquery */
sqlite3 *db = pParse->db; /* The database connection */
SrcItem *pItem; /* Use for looping over pSrcList items */
SrcItem *pMatch = 0; /* The matching pSrcList item */
NameContext *pTopNC = pNC; /* First namecontext in the list */
Schema *pSchema = 0; /* Schema of the expression */
int eNewExprOp = TK_COLUMN; /* New value for pExpr->op on success */
Table *pTab = 0; /* Table holding the row */
Column *pCol; /* A column of pTab */
ExprList *pFJMatch = 0; /* Matches for FULL JOIN .. USING */
const char *zCol = pRight->u.zToken;
assert( pNC ); /* the name context cannot be NULL. */
assert( zCol ); /* The Z in X.Y.Z cannot be NULL */
assert( zDb==0 || zTab!=0 );
assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) );
/* Initialize the node to no-match */
pExpr->iTable = -1;
ExprSetVVAProperty(pExpr, EP_NoReduce);
/* Translate the schema name in zDb into a pointer to the corresponding
** schema. If not found, pSchema will remain NULL and nothing will match
** resulting in an appropriate error message toward the end of this routine
*/
if( zDb ){
testcase( pNC->ncFlags & NC_PartIdx );
testcase( pNC->ncFlags & NC_IsCheck );
if( (pNC->ncFlags & (NC_PartIdx|NC_IsCheck))!=0 ){
/* Silently ignore database qualifiers inside CHECK constraints and
** partial indices. Do not raise errors because that might break
** legacy and because it does not hurt anything to just ignore the
** database name. */
zDb = 0;
}else{
for(i=0; i<db->nDb; i++){
assert( db->aDb[i].zDbSName );
if( sqlite3StrICmp(db->aDb[i].zDbSName,zDb)==0 ){
pSchema = db->aDb[i].pSchema;
break;
}
}
if( i==db->nDb && sqlite3StrICmp("main", zDb)==0 ){
/* This branch is taken when the main database has been renamed
** using SQLITE_DBCONFIG_MAINDBNAME. */
pSchema = db->aDb[0].pSchema;
zDb = db->aDb[0].zDbSName;
}
}
}
/* Start at the inner-most context and move outward until a match is found */
assert( pNC && cnt==0 );
do{
ExprList *pEList;
SrcList *pSrcList = pNC->pSrcList;
if( pSrcList ){
for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){
u8 hCol;
pTab = pItem->pTab;
assert( pTab!=0 && pTab->zName!=0 );
assert( pTab->nCol>0 || pParse->nErr );
assert( (int)pItem->fg.isNestedFrom == IsNestedFrom(pItem->pSelect) );
if( pItem->fg.isNestedFrom ){
/* In this case, pItem is a subquery that has been formed from a
** parenthesized subset of the FROM clause terms. Example:
** .... FROM t1 LEFT JOIN (t2 RIGHT JOIN t3 USING(x)) USING(y) ...
** \_________________________/
** This pItem -------------^
*/
int hit = 0;
assert( pItem->pSelect!=0 );
pEList = pItem->pSelect->pEList;
assert( pEList!=0 );
assert( pEList->nExpr==pTab->nCol );
for(j=0; j<pEList->nExpr; j++){
int bRowid = 0; /* True if possible rowid match */
if( !sqlite3MatchEName(&pEList->a[j], zCol, zTab, zDb, &bRowid) ){
continue;
}
if( bRowid==0 ){
if( cnt>0 ){
if( pItem->fg.isUsing==0
|| sqlite3IdListIndex(pItem->u3.pUsing, zCol)<0
){
/* Two or more tables have the same column name which is
** not joined by USING. This is an error. Signal as much
** by clearing pFJMatch and letting cnt go above 1. */
sqlite3ExprListDelete(db, pFJMatch);
pFJMatch = 0;
}else
if( (pItem->fg.jointype & JT_RIGHT)==0 ){
/* An INNER or LEFT JOIN. Use the left-most table */
continue;
}else
if( (pItem->fg.jointype & JT_LEFT)==0 ){
/* A RIGHT JOIN. Use the right-most table */
cnt = 0;
sqlite3ExprListDelete(db, pFJMatch);
pFJMatch = 0;
}else{
/* For a FULL JOIN, we must construct a coalesce() func */
extendFJMatch(pParse, &pFJMatch, pMatch, pExpr->iColumn);
}
}
cnt++;
hit = 1;
}else if( cnt>0 ){
/* This is a potential rowid match, but there has already been
** a real match found. So this can be ignored. */
continue;
}
cntTab++;
pMatch = pItem;
pExpr->iColumn = j;
pEList->a[j].fg.bUsed = 1;
/* rowid cannot be part of a USING clause - assert() this. */
assert( bRowid==0 || pEList->a[j].fg.bUsingTerm==0 );
if( pEList->a[j].fg.bUsingTerm ) break;
}
if( hit || zTab==0 ) continue;
}
assert( zDb==0 || zTab!=0 );
if( zTab ){
if( zDb ){
if( pTab->pSchema!=pSchema ) continue;
if( pSchema==0 && strcmp(zDb,"*")!=0 ) continue;
}
if( pItem->zAlias!=0 ){
if( sqlite3StrICmp(zTab, pItem->zAlias)!=0 ){
continue;
}
}else if( sqlite3StrICmp(zTab, pTab->zName)!=0 ){
if( pTab->tnum!=1 ) continue;
if( !isValidSchemaTableName(zTab, pTab, pSchema) ) continue;
}
assert( ExprUseYTab(pExpr) );
if( IN_RENAME_OBJECT && pItem->zAlias ){
sqlite3RenameTokenRemap(pParse, 0, (void*)&pExpr->y.pTab);
}
}
hCol = sqlite3StrIHash(zCol);
for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
if( pCol->hName==hCol
&& sqlite3StrICmp(pCol->zCnName, zCol)==0
){
if( cnt>0 ){
if( pItem->fg.isUsing==0
|| sqlite3IdListIndex(pItem->u3.pUsing, zCol)<0
){
/* Two or more tables have the same column name which is
** not joined by USING. This is an error. Signal as much
** by clearing pFJMatch and letting cnt go above 1. */
sqlite3ExprListDelete(db, pFJMatch);
pFJMatch = 0;
}else
if( (pItem->fg.jointype & JT_RIGHT)==0 ){
/* An INNER or LEFT JOIN. Use the left-most table */
continue;
}else
if( (pItem->fg.jointype & JT_LEFT)==0 ){
/* A RIGHT JOIN. Use the right-most table */
cnt = 0;
sqlite3ExprListDelete(db, pFJMatch);
pFJMatch = 0;
}else{
/* For a FULL JOIN, we must construct a coalesce() func */
extendFJMatch(pParse, &pFJMatch, pMatch, pExpr->iColumn);
}
}
cnt++;
pMatch = pItem;
/* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
pExpr->iColumn = j==pTab->iPKey ? -1 : (i16)j;
if( pItem->fg.isNestedFrom ){
sqlite3SrcItemColumnUsed(pItem, j);
}
break;
}
}
if( 0==cnt && VisibleRowid(pTab) ){
cntTab++;
pMatch = pItem;
}
}
if( pMatch ){
pExpr->iTable = pMatch->iCursor;
assert( ExprUseYTab(pExpr) );
pExpr->y.pTab = pMatch->pTab;
if( (pMatch->fg.jointype & (JT_LEFT|JT_LTORJ))!=0 ){
ExprSetProperty(pExpr, EP_CanBeNull);
}
pSchema = pExpr->y.pTab->pSchema;
}
} /* if( pSrcList ) */
#if !defined(SQLITE_OMIT_TRIGGER) || !defined(SQLITE_OMIT_UPSERT)
/* If we have not already resolved the name, then maybe
** it is a new.* or old.* trigger argument reference. Or
** maybe it is an excluded.* from an upsert. Or maybe it is
** a reference in the RETURNING clause to a table being modified.
*/
if( cnt==0 && zDb==0 ){
pTab = 0;
#ifndef SQLITE_OMIT_TRIGGER
if( pParse->pTriggerTab!=0 ){
int op = pParse->eTriggerOp;
assert( op==TK_DELETE || op==TK_UPDATE || op==TK_INSERT );
if( pParse->bReturning ){
if( (pNC->ncFlags & NC_UBaseReg)!=0
&& ALWAYS(zTab==0
|| sqlite3StrICmp(zTab,pParse->pTriggerTab->zName)==0)
){
pExpr->iTable = op!=TK_DELETE;
pTab = pParse->pTriggerTab;
}
}else if( op!=TK_DELETE && zTab && sqlite3StrICmp("new",zTab) == 0 ){
pExpr->iTable = 1;
pTab = pParse->pTriggerTab;
}else if( op!=TK_INSERT && zTab && sqlite3StrICmp("old",zTab)==0 ){
pExpr->iTable = 0;
pTab = pParse->pTriggerTab;
}
}
#endif /* SQLITE_OMIT_TRIGGER */
#ifndef SQLITE_OMIT_UPSERT
if( (pNC->ncFlags & NC_UUpsert)!=0 && zTab!=0 ){
Upsert *pUpsert = pNC->uNC.pUpsert;
if( pUpsert && sqlite3StrICmp("excluded",zTab)==0 ){
pTab = pUpsert->pUpsertSrc->a[0].pTab;
pExpr->iTable = EXCLUDED_TABLE_NUMBER;
}
}
#endif /* SQLITE_OMIT_UPSERT */
if( pTab ){
int iCol;
u8 hCol = sqlite3StrIHash(zCol);
pSchema = pTab->pSchema;
cntTab++;
for(iCol=0, pCol=pTab->aCol; iCol<pTab->nCol; iCol++, pCol++){
if( pCol->hName==hCol
&& sqlite3StrICmp(pCol->zCnName, zCol)==0
){
if( iCol==pTab->iPKey ){
iCol = -1;
}
break;
}
}
if( iCol>=pTab->nCol && sqlite3IsRowid(zCol) && VisibleRowid(pTab) ){
/* IMP: R-51414-32910 */
iCol = -1;
}
if( iCol<pTab->nCol ){
cnt++;
pMatch = 0;
#ifndef SQLITE_OMIT_UPSERT
if( pExpr->iTable==EXCLUDED_TABLE_NUMBER ){
testcase( iCol==(-1) );
assert( ExprUseYTab(pExpr) );
if( IN_RENAME_OBJECT ){
pExpr->iColumn = iCol;
pExpr->y.pTab = pTab;
eNewExprOp = TK_COLUMN;
}else{
pExpr->iTable = pNC->uNC.pUpsert->regData +
sqlite3TableColumnToStorage(pTab, iCol);
eNewExprOp = TK_REGISTER;
}
}else
#endif /* SQLITE_OMIT_UPSERT */
{
assert( ExprUseYTab(pExpr) );
pExpr->y.pTab = pTab;
if( pParse->bReturning ){
eNewExprOp = TK_REGISTER;
pExpr->op2 = TK_COLUMN;
pExpr->iColumn = iCol;
pExpr->iTable = pNC->uNC.iBaseReg + (pTab->nCol+1)*pExpr->iTable +
sqlite3TableColumnToStorage(pTab, iCol) + 1;
}else{
pExpr->iColumn = (i16)iCol;
eNewExprOp = TK_TRIGGER;
#ifndef SQLITE_OMIT_TRIGGER
if( iCol<0 ){
pExpr->affExpr = SQLITE_AFF_INTEGER;
}else if( pExpr->iTable==0 ){
testcase( iCol==31 );
testcase( iCol==32 );
pParse->oldmask |= (iCol>=32 ? 0xffffffff : (((u32)1)<<iCol));
}else{
testcase( iCol==31 );
testcase( iCol==32 );
pParse->newmask |= (iCol>=32 ? 0xffffffff : (((u32)1)<<iCol));
}
#endif /* SQLITE_OMIT_TRIGGER */
}
}
}
}
}
#endif /* !defined(SQLITE_OMIT_TRIGGER) || !defined(SQLITE_OMIT_UPSERT) */
/*
** Perhaps the name is a reference to the ROWID
*/
if( cnt==0
&& cntTab==1
&& pMatch
&& (pNC->ncFlags & (NC_IdxExpr|NC_GenCol))==0
&& sqlite3IsRowid(zCol)
&& ALWAYS(VisibleRowid(pMatch->pTab) || pMatch->fg.isNestedFrom)
){
cnt = 1;
if( pMatch->fg.isNestedFrom==0 ) pExpr->iColumn = -1;
pExpr->affExpr = SQLITE_AFF_INTEGER;
}
/*
** If the input is of the form Z (not Y.Z or X.Y.Z) then the name Z
** might refer to an result-set alias. This happens, for example, when
** we are resolving names in the WHERE clause of the following command:
**
** SELECT a+b AS x FROM table WHERE x<10;
**
** In cases like this, replace pExpr with a copy of the expression that
** forms the result set entry ("a+b" in the example) and return immediately.
** Note that the expression in the result set should have already been
** resolved by the time the WHERE clause is resolved.
**
** The ability to use an output result-set column in the WHERE, GROUP BY,
** or HAVING clauses, or as part of a larger expression in the ORDER BY
** clause is not standard SQL. This is a (goofy) SQLite extension, that
** is supported for backwards compatibility only. Hence, we issue a warning
** on sqlite3_log() whenever the capability is used.
*/
if( cnt==0
&& (pNC->ncFlags & NC_UEList)!=0
&& zTab==0
){
pEList = pNC->uNC.pEList;
assert( pEList!=0 );
for(j=0; j<pEList->nExpr; j++){
char *zAs = pEList->a[j].zEName;
if( pEList->a[j].fg.eEName==ENAME_NAME
&& sqlite3_stricmp(zAs, zCol)==0
){
Expr *pOrig;
assert( pExpr->pLeft==0 && pExpr->pRight==0 );
assert( ExprUseXList(pExpr)==0 || pExpr->x.pList==0 );
assert( ExprUseXSelect(pExpr)==0 || pExpr->x.pSelect==0 );
pOrig = pEList->a[j].pExpr;
if( (pNC->ncFlags&NC_AllowAgg)==0 && ExprHasProperty(pOrig, EP_Agg) ){
sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);
return WRC_Abort;
}
if( ExprHasProperty(pOrig, EP_Win)
&& ((pNC->ncFlags&NC_AllowWin)==0 || pNC!=pTopNC )
){
sqlite3ErrorMsg(pParse, "misuse of aliased window function %s",zAs);
return WRC_Abort;
}
if( sqlite3ExprVectorSize(pOrig)!=1 ){
sqlite3ErrorMsg(pParse, "row value misused");
return WRC_Abort;
}
resolveAlias(pParse, pEList, j, pExpr, nSubquery);
cnt = 1;
pMatch = 0;
assert( zTab==0 && zDb==0 );
if( IN_RENAME_OBJECT ){
sqlite3RenameTokenRemap(pParse, 0, (void*)pExpr);
}
goto lookupname_end;
}
}
}
/* Advance to the next name context. The loop will exit when either
** we have a match (cnt>0) or when we run out of name contexts.
*/
if( cnt ) break;
pNC = pNC->pNext;
nSubquery++;
}while( pNC );
/*
** If X and Y are NULL (in other words if only the column name Z is
** supplied) and the value of Z is enclosed in double-quotes, then
** Z is a string literal if it doesn't match any column names. In that
** case, we need to return right away and not make any changes to
** pExpr.
**
** Because no reference was made to outer contexts, the pNC->nRef
** fields are not changed in any context.
*/
if( cnt==0 && zTab==0 ){
assert( pExpr->op==TK_ID );
if( ExprHasProperty(pExpr,EP_DblQuoted)
&& areDoubleQuotedStringsEnabled(db, pTopNC)
){
/* If a double-quoted identifier does not match any known column name,
** then treat it as a string.
**
** This hack was added in the early days of SQLite in a misguided attempt
** to be compatible with MySQL 3.x, which used double-quotes for strings.
** I now sorely regret putting in this hack. The effect of this hack is
** that misspelled identifier names are silently converted into strings
** rather than causing an error, to the frustration of countless
** programmers. To all those frustrated programmers, my apologies.
**
** Someday, I hope to get rid of this hack. Unfortunately there is
** a huge amount of legacy SQL that uses it. So for now, we just
** issue a warning.
*/
sqlite3_log(SQLITE_WARNING,
"double-quoted string literal: \"%w\"", zCol);
#ifdef SQLITE_ENABLE_NORMALIZE
sqlite3VdbeAddDblquoteStr(db, pParse->pVdbe, zCol);
#endif
pExpr->op = TK_STRING;
memset(&pExpr->y, 0, sizeof(pExpr->y));
return WRC_Prune;
}
if( sqlite3ExprIdToTrueFalse(pExpr) ){
return WRC_Prune;
}
}
/*
** cnt==0 means there was not match.
** cnt>1 means there were two or more matches.
**
** cnt==0 is always an error. cnt>1 is often an error, but might
** be multiple matches for a NATURAL LEFT JOIN or a LEFT JOIN USING.
*/
assert( pFJMatch==0 || cnt>0 );
assert( !ExprHasProperty(pExpr, EP_xIsSelect|EP_IntValue) );
if( cnt!=1 ){
const char *zErr;
if( pFJMatch ){
if( pFJMatch->nExpr==cnt-1 ){
if( ExprHasProperty(pExpr,EP_Leaf) ){
ExprClearProperty(pExpr,EP_Leaf);
}else{
sqlite3ExprDelete(db, pExpr->pLeft);
pExpr->pLeft = 0;
sqlite3ExprDelete(db, pExpr->pRight);
pExpr->pRight = 0;
}
extendFJMatch(pParse, &pFJMatch, pMatch, pExpr->iColumn);
pExpr->op = TK_FUNCTION;
pExpr->u.zToken = "coalesce";
pExpr->x.pList = pFJMatch;
cnt = 1;
goto lookupname_end;
}else{
sqlite3ExprListDelete(db, pFJMatch);
pFJMatch = 0;
}
}
zErr = cnt==0 ? "no such column" : "ambiguous column name";
if( zDb ){
sqlite3ErrorMsg(pParse, "%s: %s.%s.%s", zErr, zDb, zTab, zCol);
}else if( zTab ){
sqlite3ErrorMsg(pParse, "%s: %s.%s", zErr, zTab, zCol);
}else if( cnt==0 && ExprHasProperty(pRight,EP_DblQuoted) ){
sqlite3ErrorMsg(pParse, "%s: \"%s\" - should this be a"
" string literal in single-quotes?",
zErr, zCol);
}else{
sqlite3ErrorMsg(pParse, "%s: %s", zErr, zCol);
}
sqlite3RecordErrorOffsetOfExpr(pParse->db, pExpr);
pParse->checkSchema = 1;
pTopNC->nNcErr++;
eNewExprOp = TK_NULL;
}
assert( pFJMatch==0 );
/* Remove all substructure from pExpr */
if( !ExprHasProperty(pExpr,(EP_TokenOnly|EP_Leaf)) ){
sqlite3ExprDelete(db, pExpr->pLeft);
pExpr->pLeft = 0;
sqlite3ExprDelete(db, pExpr->pRight);
pExpr->pRight = 0;
ExprSetProperty(pExpr, EP_Leaf);
}
/* If a column from a table in pSrcList is referenced, then record
** this fact in the pSrcList.a[].colUsed bitmask. Column 0 causes
** bit 0 to be set. Column 1 sets bit 1. And so forth. Bit 63 is
** set if the 63rd or any subsequent column is used.
**
** The colUsed mask is an optimization used to help determine if an
** index is a covering index. The correct answer is still obtained
** if the mask contains extra set bits. However, it is important to
** avoid setting bits beyond the maximum column number of the table.
** (See ticket [b92e5e8ec2cdbaa1]).
**
** If a generated column is referenced, set bits for every column
** of the table.
*/
if( pExpr->iColumn>=0 && cnt==1 && pMatch!=0 ){
pMatch->colUsed |= sqlite3ExprColUsed(pExpr);
}
pExpr->op = eNewExprOp;
lookupname_end:
if( cnt==1 ){
assert( pNC!=0 );
#ifndef SQLITE_OMIT_AUTHORIZATION
if( pParse->db->xAuth
&& (pExpr->op==TK_COLUMN || pExpr->op==TK_TRIGGER)
){
sqlite3AuthRead(pParse, pExpr, pSchema, pNC->pSrcList);
}
#endif
/* Increment the nRef value on all name contexts from TopNC up to
** the point where the name matched. */
for(;;){
assert( pTopNC!=0 );
pTopNC->nRef++;
if( pTopNC==pNC ) break;
pTopNC = pTopNC->pNext;
}
return WRC_Prune;
} else {
return WRC_Abort;
}
}
/*
** Allocate and return a pointer to an expression to load the column iCol
** from datasource iSrc in SrcList pSrc.
*/
Expr *sqlite3CreateColumnExpr(sqlite3 *db, SrcList *pSrc, int iSrc, int iCol){
Expr *p = sqlite3ExprAlloc(db, TK_COLUMN, 0, 0);
if( p ){
SrcItem *pItem = &pSrc->a[iSrc];
Table *pTab;
assert( ExprUseYTab(p) );
pTab = p->y.pTab = pItem->pTab;
p->iTable = pItem->iCursor;
if( p->y.pTab->iPKey==iCol ){
p->iColumn = -1;
}else{
p->iColumn = (ynVar)iCol;
if( (pTab->tabFlags & TF_HasGenerated)!=0
&& (pTab->aCol[iCol].colFlags & COLFLAG_GENERATED)!=0
){
testcase( pTab->nCol==63 );
testcase( pTab->nCol==64 );
pItem->colUsed = pTab->nCol>=64 ? ALLBITS : MASKBIT(pTab->nCol)-1;
}else{
testcase( iCol==BMS );
testcase( iCol==BMS-1 );
pItem->colUsed |= ((Bitmask)1)<<(iCol>=BMS ? BMS-1 : iCol);
}
}
}
return p;
}
/*
** Report an error that an expression is not valid for some set of
** pNC->ncFlags values determined by validMask.
**
** static void notValid(
** Parse *pParse, // Leave error message here
** NameContext *pNC, // The name context
** const char *zMsg, // Type of error
** int validMask, // Set of contexts for which prohibited
** Expr *pExpr // Invalidate this expression on error
** ){...}
**
** As an optimization, since the conditional is almost always false
** (because errors are rare), the conditional is moved outside of the
** function call using a macro.
*/
static void notValidImpl(
Parse *pParse, /* Leave error message here */
NameContext *pNC, /* The name context */
const char *zMsg, /* Type of error */
Expr *pExpr, /* Invalidate this expression on error */
Expr *pError /* Associate error with this expression */
){
const char *zIn = "partial index WHERE clauses";
if( pNC->ncFlags & NC_IdxExpr ) zIn = "index expressions";
#ifndef SQLITE_OMIT_CHECK
else if( pNC->ncFlags & NC_IsCheck ) zIn = "CHECK constraints";
#endif
#ifndef SQLITE_OMIT_GENERATED_COLUMNS
else if( pNC->ncFlags & NC_GenCol ) zIn = "generated columns";
#endif
sqlite3ErrorMsg(pParse, "%s prohibited in %s", zMsg, zIn);
if( pExpr ) pExpr->op = TK_NULL;
sqlite3RecordErrorOffsetOfExpr(pParse->db, pError);
}
#define sqlite3ResolveNotValid(P,N,M,X,E,R) \
assert( ((X)&~(NC_IsCheck|NC_PartIdx|NC_IdxExpr|NC_GenCol))==0 ); \
if( ((N)->ncFlags & (X))!=0 ) notValidImpl(P,N,M,E,R);
/*
** Expression p should encode a floating point value between 1.0 and 0.0.
** Return 1024 times this value. Or return -1 if p is not a floating point
** value between 1.0 and 0.0.
*/
static int exprProbability(Expr *p){
double r = -1.0;
if( p->op!=TK_FLOAT ) return -1;
assert( !ExprHasProperty(p, EP_IntValue) );
sqlite3AtoF(p->u.zToken, &r, sqlite3Strlen30(p->u.zToken), SQLITE_UTF8);
assert( r>=0.0 );
if( r>1.0 ) return -1;
return (int)(r*134217728.0);
}
/*
** This routine is callback for sqlite3WalkExpr().
**
** Resolve symbolic names into TK_COLUMN operators for the current
** node in the expression tree. Return 0 to continue the search down
** the tree or 2 to abort the tree walk.
**
** This routine also does error checking and name resolution for
** function names. The operator for aggregate functions is changed
** to TK_AGG_FUNCTION.
*/
static int resolveExprStep(Walker *pWalker, Expr *pExpr){
NameContext *pNC;
Parse *pParse;
pNC = pWalker->u.pNC;
assert( pNC!=0 );
pParse = pNC->pParse;
assert( pParse==pWalker->pParse );
#ifndef NDEBUG
if( pNC->pSrcList && pNC->pSrcList->nAlloc>0 ){
SrcList *pSrcList = pNC->pSrcList;
int i;
for(i=0; i<pNC->pSrcList->nSrc; i++){
assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab);
}
}
#endif
switch( pExpr->op ){
/* The special operator TK_ROW means use the rowid for the first
** column in the FROM clause. This is used by the LIMIT and ORDER BY
** clause processing on UPDATE and DELETE statements, and by
** UPDATE ... FROM statement processing.
*/
case TK_ROW: {
SrcList *pSrcList = pNC->pSrcList;
SrcItem *pItem;
assert( pSrcList && pSrcList->nSrc>=1 );
pItem = pSrcList->a;
pExpr->op = TK_COLUMN;
assert( ExprUseYTab(pExpr) );
pExpr->y.pTab = pItem->pTab;
pExpr->iTable = pItem->iCursor;
pExpr->iColumn--;
pExpr->affExpr = SQLITE_AFF_INTEGER;
break;
}
/* An optimization: Attempt to convert
**
** "expr IS NOT NULL" --> "TRUE"
** "expr IS NULL" --> "FALSE"
**
** if we can prove that "expr" is never NULL. Call this the
** "NOT NULL strength reduction optimization".
**
** If this optimization occurs, also restore the NameContext ref-counts
** to the state they where in before the "column" LHS expression was
** resolved. This prevents "column" from being counted as having been
** referenced, which might prevent a SELECT from being erroneously
** marked as correlated.
*/
case TK_NOTNULL:
case TK_ISNULL: {
int anRef[8];
NameContext *p;
int i;
for(i=0, p=pNC; p && i<ArraySize(anRef); p=p->pNext, i++){
anRef[i] = p->nRef;
}
sqlite3WalkExpr(pWalker, pExpr->pLeft);
if( 0==sqlite3ExprCanBeNull(pExpr->pLeft) && !IN_RENAME_OBJECT ){
testcase( ExprHasProperty(pExpr, EP_OuterON) );
assert( !ExprHasProperty(pExpr, EP_IntValue) );
pExpr->u.iValue = (pExpr->op==TK_NOTNULL);
pExpr->flags |= EP_IntValue;
pExpr->op = TK_INTEGER;
for(i=0, p=pNC; p && i<ArraySize(anRef); p=p->pNext, i++){
p->nRef = anRef[i];
}
sqlite3ExprDelete(pParse->db, pExpr->pLeft);
pExpr->pLeft = 0;
}
return WRC_Prune;
}
/* A column name: ID
** Or table name and column name: ID.ID
** Or a database, table and column: ID.ID.ID
**
** The TK_ID and TK_OUT cases are combined so that there will only
** be one call to lookupName(). Then the compiler will in-line
** lookupName() for a size reduction and performance increase.
*/
case TK_ID:
case TK_DOT: {
const char *zTable;
const char *zDb;
Expr *pRight;
if( pExpr->op==TK_ID ){
zDb = 0;
zTable = 0;
assert( !ExprHasProperty(pExpr, EP_IntValue) );
pRight = pExpr;
}else{
Expr *pLeft = pExpr->pLeft;
testcase( pNC->ncFlags & NC_IdxExpr );
testcase( pNC->ncFlags & NC_GenCol );
sqlite3ResolveNotValid(pParse, pNC, "the \".\" operator",
NC_IdxExpr|NC_GenCol, 0, pExpr);
pRight = pExpr->pRight;
if( pRight->op==TK_ID ){
zDb = 0;
}else{
assert( pRight->op==TK_DOT );
assert( !ExprHasProperty(pRight, EP_IntValue) );
zDb = pLeft->u.zToken;
pLeft = pRight->pLeft;
pRight = pRight->pRight;
}
assert( ExprUseUToken(pLeft) && ExprUseUToken(pRight) );
zTable = pLeft->u.zToken;
assert( ExprUseYTab(pExpr) );
if( IN_RENAME_OBJECT ){
sqlite3RenameTokenRemap(pParse, (void*)pExpr, (void*)pRight);
sqlite3RenameTokenRemap(pParse, (void*)&pExpr->y.pTab, (void*)pLeft);
}
}
return lookupName(pParse, zDb, zTable, pRight, pNC, pExpr);
}
/* Resolve function names
*/
case TK_FUNCTION: {
ExprList *pList = pExpr->x.pList; /* The argument list */
int n = pList ? pList->nExpr : 0; /* Number of arguments */
int no_such_func = 0; /* True if no such function exists */
int wrong_num_args = 0; /* True if wrong number of arguments */
int is_agg = 0; /* True if is an aggregate function */
const char *zId; /* The function name. */
FuncDef *pDef; /* Information about the function */
u8 enc = ENC(pParse->db); /* The database encoding */
int savedAllowFlags = (pNC->ncFlags & (NC_AllowAgg | NC_AllowWin));
#ifndef SQLITE_OMIT_WINDOWFUNC
Window *pWin = (IsWindowFunc(pExpr) ? pExpr->y.pWin : 0);
#endif
assert( !ExprHasProperty(pExpr, EP_xIsSelect|EP_IntValue) );
assert( pExpr->pLeft==0 || pExpr->pLeft->op==TK_ORDER );
zId = pExpr->u.zToken;
pDef = sqlite3FindFunction(pParse->db, zId, n, enc, 0);
if( pDef==0 ){
pDef = sqlite3FindFunction(pParse->db, zId, -2, enc, 0);
if( pDef==0 ){
no_such_func = 1;
}else{
wrong_num_args = 1;
}
}else{
is_agg = pDef->xFinalize!=0;
if( pDef->funcFlags & SQLITE_FUNC_UNLIKELY ){
ExprSetProperty(pExpr, EP_Unlikely);
if( n==2 ){
pExpr->iTable = exprProbability(pList->a[1].pExpr);
if( pExpr->iTable<0 ){
sqlite3ErrorMsg(pParse,
"second argument to %#T() must be a "
"constant between 0.0 and 1.0", pExpr);
pNC->nNcErr++;
}
}else{
/* EVIDENCE-OF: R-61304-29449 The unlikely(X) function is
** equivalent to likelihood(X, 0.0625).
** EVIDENCE-OF: R-01283-11636 The unlikely(X) function is
** short-hand for likelihood(X,0.0625).
** EVIDENCE-OF: R-36850-34127 The likely(X) function is short-hand
** for likelihood(X,0.9375).
** EVIDENCE-OF: R-53436-40973 The likely(X) function is equivalent
** to likelihood(X,0.9375). */
/* TUNING: unlikely() probability is 0.0625. likely() is 0.9375 */
pExpr->iTable = pDef->zName[0]=='u' ? 8388608 : 125829120;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int auth = sqlite3AuthCheck(pParse, SQLITE_FUNCTION, 0,pDef->zName,0);
if( auth!=SQLITE_OK ){
if( auth==SQLITE_DENY ){
sqlite3ErrorMsg(pParse, "not authorized to use function: %#T",
pExpr);
pNC->nNcErr++;
}
pExpr->op = TK_NULL;
return WRC_Prune;
}
}
#endif
if( pDef->funcFlags & (SQLITE_FUNC_CONSTANT|SQLITE_FUNC_SLOCHNG) ){
/* For the purposes of the EP_ConstFunc flag, date and time
** functions and other functions that change slowly are considered
** constant because they are constant for the duration of one query.
** This allows them to be factored out of inner loops. */
ExprSetProperty(pExpr,EP_ConstFunc);
}
if( (pDef->funcFlags & SQLITE_FUNC_CONSTANT)==0 ){
/* Clearly non-deterministic functions like random(), but also
** date/time functions that use 'now', and other functions like
** sqlite_version() that might change over time cannot be used
** in an index or generated column. Curiously, they can be used
** in a CHECK constraint. SQLServer, MySQL, and PostgreSQL all
** all this. */
sqlite3ResolveNotValid(pParse, pNC, "non-deterministic functions",
NC_IdxExpr|NC_PartIdx|NC_GenCol, 0, pExpr);
}else{
assert( (NC_SelfRef & 0xff)==NC_SelfRef ); /* Must fit in 8 bits */
pExpr->op2 = pNC->ncFlags & NC_SelfRef;
if( pNC->ncFlags & NC_FromDDL ) ExprSetProperty(pExpr, EP_FromDDL);
}
if( (pDef->funcFlags & SQLITE_FUNC_INTERNAL)!=0
&& pParse->nested==0
&& (pParse->db->mDbFlags & DBFLAG_InternalFunc)==0
){
/* Internal-use-only functions are disallowed unless the
** SQL is being compiled using sqlite3NestedParse() or
** the SQLITE_TESTCTRL_INTERNAL_FUNCTIONS test-control has be
** used to activate internal functions for testing purposes */
no_such_func = 1;
pDef = 0;
}else
if( (pDef->funcFlags & (SQLITE_FUNC_DIRECT|SQLITE_FUNC_UNSAFE))!=0
&& !IN_RENAME_OBJECT
){
sqlite3ExprFunctionUsable(pParse, pExpr, pDef);
}
}
if( 0==IN_RENAME_OBJECT ){
#ifndef SQLITE_OMIT_WINDOWFUNC
assert( is_agg==0 || (pDef->funcFlags & SQLITE_FUNC_MINMAX)
|| (pDef->xValue==0 && pDef->xInverse==0)
|| (pDef->xValue && pDef->xInverse && pDef->xSFunc && pDef->xFinalize)
);
if( pDef && pDef->xValue==0 && pWin ){
sqlite3ErrorMsg(pParse,
"%#T() may not be used as a window function", pExpr
);
pNC->nNcErr++;
}else if(
(is_agg && (pNC->ncFlags & NC_AllowAgg)==0)
|| (is_agg && (pDef->funcFlags&SQLITE_FUNC_WINDOW) && !pWin)
|| (is_agg && pWin && (pNC->ncFlags & NC_AllowWin)==0)
){
const char *zType;
if( (pDef->funcFlags & SQLITE_FUNC_WINDOW) || pWin ){
zType = "window";
}else{
zType = "aggregate";
}
sqlite3ErrorMsg(pParse, "misuse of %s function %#T()",zType,pExpr);
pNC->nNcErr++;
is_agg = 0;
}
#else
if( (is_agg && (pNC->ncFlags & NC_AllowAgg)==0) ){
sqlite3ErrorMsg(pParse,"misuse of aggregate function %#T()",pExpr);
pNC->nNcErr++;
is_agg = 0;
}
#endif
else if( no_such_func && pParse->db->init.busy==0
#ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
&& pParse->explain==0
#endif
){
sqlite3ErrorMsg(pParse, "no such function: %#T", pExpr);
pNC->nNcErr++;
}else if( wrong_num_args ){
sqlite3ErrorMsg(pParse,"wrong number of arguments to function %#T()",
pExpr);
pNC->nNcErr++;
}
#ifndef SQLITE_OMIT_WINDOWFUNC
else if( is_agg==0 && ExprHasProperty(pExpr, EP_WinFunc) ){
sqlite3ErrorMsg(pParse,
"FILTER may not be used with non-aggregate %#T()",
pExpr
);
pNC->nNcErr++;
}
#endif
else if( is_agg==0 && pExpr->pLeft ){
sqlite3ExprOrderByAggregateError(pParse, pExpr);
pNC->nNcErr++;
}
if( is_agg ){
/* Window functions may not be arguments of aggregate functions.
** Or arguments of other window functions. But aggregate functions
** may be arguments for window functions. */
#ifndef SQLITE_OMIT_WINDOWFUNC
pNC->ncFlags &= ~(NC_AllowWin | (!pWin ? NC_AllowAgg : 0));
#else
pNC->ncFlags &= ~NC_AllowAgg;
#endif
}
}
#ifndef SQLITE_OMIT_WINDOWFUNC
else if( ExprHasProperty(pExpr, EP_WinFunc) ){
is_agg = 1;
}
#endif
sqlite3WalkExprList(pWalker, pList);
if( is_agg ){
if( pExpr->pLeft ){
assert( pExpr->pLeft->op==TK_ORDER );
assert( ExprUseXList(pExpr->pLeft) );
sqlite3WalkExprList(pWalker, pExpr->pLeft->x.pList);
}
#ifndef SQLITE_OMIT_WINDOWFUNC
if( pWin ){
Select *pSel = pNC->pWinSelect;
assert( pWin==0 || (ExprUseYWin(pExpr) && pWin==pExpr->y.pWin) );
if( IN_RENAME_OBJECT==0 ){
sqlite3WindowUpdate(pParse, pSel ? pSel->pWinDefn : 0, pWin, pDef);
if( pParse->db->mallocFailed ) break;
}
sqlite3WalkExprList(pWalker, pWin->pPartition);
sqlite3WalkExprList(pWalker, pWin->pOrderBy);
sqlite3WalkExpr(pWalker, pWin->pFilter);
sqlite3WindowLink(pSel, pWin);
pNC->ncFlags |= NC_HasWin;
}else
#endif /* SQLITE_OMIT_WINDOWFUNC */
{
NameContext *pNC2; /* For looping up thru outer contexts */
pExpr->op = TK_AGG_FUNCTION;
pExpr->op2 = 0;
#ifndef SQLITE_OMIT_WINDOWFUNC
if( ExprHasProperty(pExpr, EP_WinFunc) ){
sqlite3WalkExpr(pWalker, pExpr->y.pWin->pFilter);
}
#endif
pNC2 = pNC;
while( pNC2
&& sqlite3ReferencesSrcList(pParse, pExpr, pNC2->pSrcList)==0
){
pExpr->op2 += (1 + pNC2->nNestedSelect);
pNC2 = pNC2->pNext;
}
assert( pDef!=0 || IN_RENAME_OBJECT );
if( pNC2 && pDef ){
pExpr->op2 += pNC2->nNestedSelect;
assert( SQLITE_FUNC_MINMAX==NC_MinMaxAgg );
assert( SQLITE_FUNC_ANYORDER==NC_OrderAgg );
testcase( (pDef->funcFlags & SQLITE_FUNC_MINMAX)!=0 );
testcase( (pDef->funcFlags & SQLITE_FUNC_ANYORDER)!=0 );
pNC2->ncFlags |= NC_HasAgg
| ((pDef->funcFlags^SQLITE_FUNC_ANYORDER)
& (SQLITE_FUNC_MINMAX|SQLITE_FUNC_ANYORDER));
}
}
pNC->ncFlags |= savedAllowFlags;
}
/* FIX ME: Compute pExpr->affinity based on the expected return
** type of the function
*/
return WRC_Prune;
}
#ifndef SQLITE_OMIT_SUBQUERY
case TK_SELECT:
case TK_EXISTS: testcase( pExpr->op==TK_EXISTS );
#endif
case TK_IN: {
testcase( pExpr->op==TK_IN );
if( ExprUseXSelect(pExpr) ){
int nRef = pNC->nRef;
testcase( pNC->ncFlags & NC_IsCheck );
testcase( pNC->ncFlags & NC_PartIdx );
testcase( pNC->ncFlags & NC_IdxExpr );
testcase( pNC->ncFlags & NC_GenCol );
if( pNC->ncFlags & NC_SelfRef ){
notValidImpl(pParse, pNC, "subqueries", pExpr, pExpr);
}else{
sqlite3WalkSelect(pWalker, pExpr->x.pSelect);
}
assert( pNC->nRef>=nRef );
if( nRef!=pNC->nRef ){
ExprSetProperty(pExpr, EP_VarSelect);
}
pNC->ncFlags |= NC_Subquery;
}
break;
}
case TK_VARIABLE: {
testcase( pNC->ncFlags & NC_IsCheck );
testcase( pNC->ncFlags & NC_PartIdx );
testcase( pNC->ncFlags & NC_IdxExpr );
testcase( pNC->ncFlags & NC_GenCol );
sqlite3ResolveNotValid(pParse, pNC, "parameters",
NC_IsCheck|NC_PartIdx|NC_IdxExpr|NC_GenCol, pExpr, pExpr);
break;
}
case TK_IS:
case TK_ISNOT: {
Expr *pRight = sqlite3ExprSkipCollateAndLikely(pExpr->pRight);
assert( !ExprHasProperty(pExpr, EP_Reduced) );
/* Handle special cases of "x IS TRUE", "x IS FALSE", "x IS NOT TRUE",
** and "x IS NOT FALSE". */
if( ALWAYS(pRight) && (pRight->op==TK_ID || pRight->op==TK_TRUEFALSE) ){
int rc = resolveExprStep(pWalker, pRight);
if( rc==WRC_Abort ) return WRC_Abort;
if( pRight->op==TK_TRUEFALSE ){
pExpr->op2 = pExpr->op;
pExpr->op = TK_TRUTH;
return WRC_Continue;
}
}
/* no break */ deliberate_fall_through
}
case TK_BETWEEN:
case TK_EQ:
case TK_NE:
case TK_LT:
case TK_LE:
case TK_GT:
case TK_GE: {
int nLeft, nRight;
if( pParse->db->mallocFailed ) break;
assert( pExpr->pLeft!=0 );
nLeft = sqlite3ExprVectorSize(pExpr->pLeft);
if( pExpr->op==TK_BETWEEN ){
assert( ExprUseXList(pExpr) );
nRight = sqlite3ExprVectorSize(pExpr->x.pList->a[0].pExpr);
if( nRight==nLeft ){
nRight = sqlite3ExprVectorSize(pExpr->x.pList->a[1].pExpr);
}
}else{
assert( pExpr->pRight!=0 );
nRight = sqlite3ExprVectorSize(pExpr->pRight);
}
if( nLeft!=nRight ){
testcase( pExpr->op==TK_EQ );
testcase( pExpr->op==TK_NE );
testcase( pExpr->op==TK_LT );
testcase( pExpr->op==TK_LE );
testcase( pExpr->op==TK_GT );
testcase( pExpr->op==TK_GE );
testcase( pExpr->op==TK_IS );
testcase( pExpr->op==TK_ISNOT );
testcase( pExpr->op==TK_BETWEEN );
sqlite3ErrorMsg(pParse, "row value misused");
sqlite3RecordErrorOffsetOfExpr(pParse->db, pExpr);
}
break;
}
}
assert( pParse->db->mallocFailed==0 || pParse->nErr!=0 );
return pParse->nErr ? WRC_Abort : WRC_Continue;
}
/*
** pEList is a list of expressions which are really the result set of the
** a SELECT statement. pE is a term in an ORDER BY or GROUP BY clause.
** This routine checks to see if pE is a simple identifier which corresponds
** to the AS-name of one of the terms of the expression list. If it is,
** this routine return an integer between 1 and N where N is the number of
** elements in pEList, corresponding to the matching entry. If there is
** no match, or if pE is not a simple identifier, then this routine
** return 0.
**
** pEList has been resolved. pE has not.
*/
static int resolveAsName(
Parse *pParse, /* Parsing context for error messages */
ExprList *pEList, /* List of expressions to scan */
Expr *pE /* Expression we are trying to match */
){
int i; /* Loop counter */
UNUSED_PARAMETER(pParse);
if( pE->op==TK_ID ){
const char *zCol;
assert( !ExprHasProperty(pE, EP_IntValue) );
zCol = pE->u.zToken;
for(i=0; i<pEList->nExpr; i++){
if( pEList->a[i].fg.eEName==ENAME_NAME
&& sqlite3_stricmp(pEList->a[i].zEName, zCol)==0
){
return i+1;
}
}
}
return 0;
}
/*
** pE is a pointer to an expression which is a single term in the
** ORDER BY of a compound SELECT. The expression has not been
** name resolved.
**
** At the point this routine is called, we already know that the
** ORDER BY term is not an integer index into the result set. That
** case is handled by the calling routine.
**
** Attempt to match pE against result set columns in the left-most
** SELECT statement. Return the index i of the matching column,
** as an indication to the caller that it should sort by the i-th column.
** The left-most column is 1. In other words, the value returned is the
** same integer value that would be used in the SQL statement to indicate
** the column.
**
** If there is no match, return 0. Return -1 if an error occurs.
*/
static int resolveOrderByTermToExprList(
Parse *pParse, /* Parsing context for error messages */
Select *pSelect, /* The SELECT statement with the ORDER BY clause */
Expr *pE /* The specific ORDER BY term */
){
int i; /* Loop counter */
ExprList *pEList; /* The columns of the result set */
NameContext nc; /* Name context for resolving pE */
sqlite3 *db; /* Database connection */
int rc; /* Return code from subprocedures */
u8 savedSuppErr; /* Saved value of db->suppressErr */
assert( sqlite3ExprIsInteger(pE, &i)==0 );
pEList = pSelect->pEList;
/* Resolve all names in the ORDER BY term expression
*/
memset(&nc, 0, sizeof(nc));
nc.pParse = pParse;
nc.pSrcList = pSelect->pSrc;
nc.uNC.pEList = pEList;
nc.ncFlags = NC_AllowAgg|NC_UEList|NC_NoSelect;
nc.nNcErr = 0;
db = pParse->db;
savedSuppErr = db->suppressErr;
db->suppressErr = 1;
rc = sqlite3ResolveExprNames(&nc, pE);
db->suppressErr = savedSuppErr;
if( rc ) return 0;
/* Try to match the ORDER BY expression against an expression
** in the result set. Return an 1-based index of the matching
** result-set entry.
*/
for(i=0; i<pEList->nExpr; i++){
if( sqlite3ExprCompare(0, pEList->a[i].pExpr, pE, -1)<2 ){
return i+1;
}
}
/* If no match, return 0. */
return 0;
}
/*
** Generate an ORDER BY or GROUP BY term out-of-range error.
*/
static void resolveOutOfRangeError(
Parse *pParse, /* The error context into which to write the error */
const char *zType, /* "ORDER" or "GROUP" */
int i, /* The index (1-based) of the term out of range */
int mx, /* Largest permissible value of i */
Expr *pError /* Associate the error with the expression */
){
sqlite3ErrorMsg(pParse,
"%r %s BY term out of range - should be "
"between 1 and %d", i, zType, mx);
sqlite3RecordErrorOffsetOfExpr(pParse->db, pError);
}
/*
** Analyze the ORDER BY clause in a compound SELECT statement. Modify
** each term of the ORDER BY clause is a constant integer between 1
** and N where N is the number of columns in the compound SELECT.
**
** ORDER BY terms that are already an integer between 1 and N are
** unmodified. ORDER BY terms that are integers outside the range of
** 1 through N generate an error. ORDER BY terms that are expressions
** are matched against result set expressions of compound SELECT
** beginning with the left-most SELECT and working toward the right.
** At the first match, the ORDER BY expression is transformed into
** the integer column number.
**
** Return the number of errors seen.
*/
static int resolveCompoundOrderBy(
Parse *pParse, /* Parsing context. Leave error messages here */
Select *pSelect /* The SELECT statement containing the ORDER BY */
){
int i;
ExprList *pOrderBy;
ExprList *pEList;
sqlite3 *db;
int moreToDo = 1;
pOrderBy = pSelect->pOrderBy;
if( pOrderBy==0 ) return 0;
db = pParse->db;
if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){
sqlite3ErrorMsg(pParse, "too many terms in ORDER BY clause");
return 1;
}
for(i=0; i<pOrderBy->nExpr; i++){
pOrderBy->a[i].fg.done = 0;
}
pSelect->pNext = 0;
while( pSelect->pPrior ){
pSelect->pPrior->pNext = pSelect;
pSelect = pSelect->pPrior;
}
while( pSelect && moreToDo ){
struct ExprList_item *pItem;
moreToDo = 0;
pEList = pSelect->pEList;
assert( pEList!=0 );
for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){
int iCol = -1;
Expr *pE, *pDup;
if( pItem->fg.done ) continue;
pE = sqlite3ExprSkipCollateAndLikely(pItem->pExpr);
if( NEVER(pE==0) ) continue;
if( sqlite3ExprIsInteger(pE, &iCol) ){
if( iCol<=0 || iCol>pEList->nExpr ){
resolveOutOfRangeError(pParse, "ORDER", i+1, pEList->nExpr, pE);
return 1;
}
}else{
iCol = resolveAsName(pParse, pEList, pE);
if( iCol==0 ){
/* Now test if expression pE matches one of the values returned
** by pSelect. In the usual case this is done by duplicating the
** expression, resolving any symbols in it, and then comparing
** it against each expression returned by the SELECT statement.
** Once the comparisons are finished, the duplicate expression
** is deleted.
**
** If this is running as part of an ALTER TABLE operation and
** the symbols resolve successfully, also resolve the symbols in the
** actual expression. This allows the code in alter.c to modify
** column references within the ORDER BY expression as required. */
pDup = sqlite3ExprDup(db, pE, 0);
if( !db->mallocFailed ){
assert(pDup);
iCol = resolveOrderByTermToExprList(pParse, pSelect, pDup);
if( IN_RENAME_OBJECT && iCol>0 ){
resolveOrderByTermToExprList(pParse, pSelect, pE);
}
}
sqlite3ExprDelete(db, pDup);
}
}
if( iCol>0 ){
/* Convert the ORDER BY term into an integer column number iCol,
** taking care to preserve the COLLATE clause if it exists. */
if( !IN_RENAME_OBJECT ){
Expr *pNew = sqlite3Expr(db, TK_INTEGER, 0);
if( pNew==0 ) return 1;
pNew->flags |= EP_IntValue;
pNew->u.iValue = iCol;
if( pItem->pExpr==pE ){
pItem->pExpr = pNew;
}else{
Expr *pParent = pItem->pExpr;
assert( pParent->op==TK_COLLATE );
while( pParent->pLeft->op==TK_COLLATE ) pParent = pParent->pLeft;
assert( pParent->pLeft==pE );
pParent->pLeft = pNew;
}
sqlite3ExprDelete(db, pE);
pItem->u.x.iOrderByCol = (u16)iCol;
}
pItem->fg.done = 1;
}else{
moreToDo = 1;
}
}
pSelect = pSelect->pNext;
}
for(i=0; i<pOrderBy->nExpr; i++){
if( pOrderBy->a[i].fg.done==0 ){
sqlite3ErrorMsg(pParse, "%r ORDER BY term does not match any "
"column in the result set", i+1);
return 1;
}
}
return 0;
}
/*
** Check every term in the ORDER BY or GROUP BY clause pOrderBy of
** the SELECT statement pSelect. If any term is reference to a
** result set expression (as determined by the ExprList.a.u.x.iOrderByCol
** field) then convert that term into a copy of the corresponding result set
** column.
**
** If any errors are detected, add an error message to pParse and
** return non-zero. Return zero if no errors are seen.
*/
int sqlite3ResolveOrderGroupBy(
Parse *pParse, /* Parsing context. Leave error messages here */
Select *pSelect, /* The SELECT statement containing the clause */
ExprList *pOrderBy, /* The ORDER BY or GROUP BY clause to be processed */
const char *zType /* "ORDER" or "GROUP" */
){
int i;
sqlite3 *db = pParse->db;
ExprList *pEList;
struct ExprList_item *pItem;
if( pOrderBy==0 || pParse->db->mallocFailed || IN_RENAME_OBJECT ) return 0;
if( pOrderBy->nExpr>db->aLimit[SQLITE_LIMIT_COLUMN] ){
sqlite3ErrorMsg(pParse, "too many terms in %s BY clause", zType);
return 1;
}
pEList = pSelect->pEList;
assert( pEList!=0 ); /* sqlite3SelectNew() guarantees this */
for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){
if( pItem->u.x.iOrderByCol ){
if( pItem->u.x.iOrderByCol>pEList->nExpr ){
resolveOutOfRangeError(pParse, zType, i+1, pEList->nExpr, 0);
return 1;
}
resolveAlias(pParse, pEList, pItem->u.x.iOrderByCol-1, pItem->pExpr,0);
}
}
return 0;
}
#ifndef SQLITE_OMIT_WINDOWFUNC
/*
** Walker callback for windowRemoveExprFromSelect().
*/
static int resolveRemoveWindowsCb(Walker *pWalker, Expr *pExpr){
UNUSED_PARAMETER(pWalker);
if( ExprHasProperty(pExpr, EP_WinFunc) ){
Window *pWin = pExpr->y.pWin;
sqlite3WindowUnlinkFromSelect(pWin);
}
return WRC_Continue;
}
/*
** Remove any Window objects owned by the expression pExpr from the
** Select.pWin list of Select object pSelect.
*/
static void windowRemoveExprFromSelect(Select *pSelect, Expr *pExpr){
if( pSelect->pWin ){
Walker sWalker;
memset(&sWalker, 0, sizeof(Walker));
sWalker.xExprCallback = resolveRemoveWindowsCb;
sWalker.u.pSelect = pSelect;
sqlite3WalkExpr(&sWalker, pExpr);
}
}
#else
# define windowRemoveExprFromSelect(a, b)
#endif /* SQLITE_OMIT_WINDOWFUNC */
/*
** pOrderBy is an ORDER BY or GROUP BY clause in SELECT statement pSelect.
** The Name context of the SELECT statement is pNC. zType is either
** "ORDER" or "GROUP" depending on which type of clause pOrderBy is.
**
** This routine resolves each term of the clause into an expression.
** If the order-by term is an integer I between 1 and N (where N is the
** number of columns in the result set of the SELECT) then the expression
** in the resolution is a copy of the I-th result-set expression. If
** the order-by term is an identifier that corresponds to the AS-name of
** a result-set expression, then the term resolves to a copy of the
** result-set expression. Otherwise, the expression is resolved in
** the usual way - using sqlite3ResolveExprNames().
**
** This routine returns the number of errors. If errors occur, then
** an appropriate error message might be left in pParse. (OOM errors
** excepted.)
*/
static int resolveOrderGroupBy(
NameContext *pNC, /* The name context of the SELECT statement */
Select *pSelect, /* The SELECT statement holding pOrderBy */
ExprList *pOrderBy, /* An ORDER BY or GROUP BY clause to resolve */
const char *zType /* Either "ORDER" or "GROUP", as appropriate */
){
int i, j; /* Loop counters */
int iCol; /* Column number */
struct ExprList_item *pItem; /* A term of the ORDER BY clause */
Parse *pParse; /* Parsing context */
int nResult; /* Number of terms in the result set */
assert( pOrderBy!=0 );
nResult = pSelect->pEList->nExpr;
pParse = pNC->pParse;
for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){
Expr *pE = pItem->pExpr;
Expr *pE2 = sqlite3ExprSkipCollateAndLikely(pE);
if( NEVER(pE2==0) ) continue;
if( zType[0]!='G' ){
iCol = resolveAsName(pParse, pSelect->pEList, pE2);
if( iCol>0 ){
/* If an AS-name match is found, mark this ORDER BY column as being
** a copy of the iCol-th result-set column. The subsequent call to
** sqlite3ResolveOrderGroupBy() will convert the expression to a
** copy of the iCol-th result-set expression. */
pItem->u.x.iOrderByCol = (u16)iCol;
continue;
}
}
if( sqlite3ExprIsInteger(pE2, &iCol) ){
/* The ORDER BY term is an integer constant. Again, set the column
** number so that sqlite3ResolveOrderGroupBy() will convert the
** order-by term to a copy of the result-set expression */
if( iCol<1 || iCol>0xffff ){
resolveOutOfRangeError(pParse, zType, i+1, nResult, pE2);
return 1;
}
pItem->u.x.iOrderByCol = (u16)iCol;
continue;
}
/* Otherwise, treat the ORDER BY term as an ordinary expression */
pItem->u.x.iOrderByCol = 0;
if( sqlite3ResolveExprNames(pNC, pE) ){
return 1;
}
for(j=0; j<pSelect->pEList->nExpr; j++){
if( sqlite3ExprCompare(0, pE, pSelect->pEList->a[j].pExpr, -1)==0 ){
/* Since this expression is being changed into a reference
** to an identical expression in the result set, remove all Window
** objects belonging to the expression from the Select.pWin list. */
windowRemoveExprFromSelect(pSelect, pE);
pItem->u.x.iOrderByCol = j+1;
}
}
}
return sqlite3ResolveOrderGroupBy(pParse, pSelect, pOrderBy, zType);
}
/*
** Resolve names in the SELECT statement p and all of its descendants.
*/
static int resolveSelectStep(Walker *pWalker, Select *p){
NameContext *pOuterNC; /* Context that contains this SELECT */
NameContext sNC; /* Name context of this SELECT */
int isCompound; /* True if p is a compound select */
int nCompound; /* Number of compound terms processed so far */
Parse *pParse; /* Parsing context */
int i; /* Loop counter */
ExprList *pGroupBy; /* The GROUP BY clause */
Select *pLeftmost; /* Left-most of SELECT of a compound */
sqlite3 *db; /* Database connection */
assert( p!=0 );
if( p->selFlags & SF_Resolved ){
return WRC_Prune;
}
pOuterNC = pWalker->u.pNC;
pParse = pWalker->pParse;
db = pParse->db;
/* Normally sqlite3SelectExpand() will be called first and will have
** already expanded this SELECT. However, if this is a subquery within
** an expression, sqlite3ResolveExprNames() will be called without a
** prior call to sqlite3SelectExpand(). When that happens, let
** sqlite3SelectPrep() do all of the processing for this SELECT.
** sqlite3SelectPrep() will invoke both sqlite3SelectExpand() and
** this routine in the correct order.
*/
if( (p->selFlags & SF_Expanded)==0 ){
sqlite3SelectPrep(pParse, p, pOuterNC);
return pParse->nErr ? WRC_Abort : WRC_Prune;
}
isCompound = p->pPrior!=0;
nCompound = 0;
pLeftmost = p;
while( p ){
assert( (p->selFlags & SF_Expanded)!=0 );
assert( (p->selFlags & SF_Resolved)==0 );
p->selFlags |= SF_Resolved;
/* Resolve the expressions in the LIMIT and OFFSET clauses. These
** are not allowed to refer to any names, so pass an empty NameContext.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pWinSelect = p;
if( sqlite3ResolveExprNames(&sNC, p->pLimit) ){
return WRC_Abort;
}
/* If the SF_Converted flags is set, then this Select object was
** was created by the convertCompoundSelectToSubquery() function.
** In this case the ORDER BY clause (p->pOrderBy) should be resolved
** as if it were part of the sub-query, not the parent. This block
** moves the pOrderBy down to the sub-query. It will be moved back
** after the names have been resolved. */
if( p->selFlags & SF_Converted ){
Select *pSub = p->pSrc->a[0].pSelect;
assert( p->pSrc->nSrc==1 && p->pOrderBy );
assert( pSub->pPrior && pSub->pOrderBy==0 );
pSub->pOrderBy = p->pOrderBy;
p->pOrderBy = 0;
}
/* Recursively resolve names in all subqueries in the FROM clause
*/
if( pOuterNC ) pOuterNC->nNestedSelect++;
for(i=0; i<p->pSrc->nSrc; i++){
SrcItem *pItem = &p->pSrc->a[i];
if( pItem->pSelect && (pItem->pSelect->selFlags & SF_Resolved)==0 ){
int nRef = pOuterNC ? pOuterNC->nRef : 0;
const char *zSavedContext = pParse->zAuthContext;
if( pItem->zName ) pParse->zAuthContext = pItem->zName;
sqlite3ResolveSelectNames(pParse, pItem->pSelect, pOuterNC);
pParse->zAuthContext = zSavedContext;
if( pParse->nErr ) return WRC_Abort;
assert( db->mallocFailed==0 );
/* If the number of references to the outer context changed when
** expressions in the sub-select were resolved, the sub-select
** is correlated. It is not required to check the refcount on any
** but the innermost outer context object, as lookupName() increments
** the refcount on all contexts between the current one and the
** context containing the column when it resolves a name. */
if( pOuterNC ){
assert( pItem->fg.isCorrelated==0 && pOuterNC->nRef>=nRef );
pItem->fg.isCorrelated = (pOuterNC->nRef>nRef);
}
}
}
if( pOuterNC && ALWAYS(pOuterNC->nNestedSelect>0) ){
pOuterNC->nNestedSelect--;
}
/* Set up the local name-context to pass to sqlite3ResolveExprNames() to
** resolve the result-set expression list.
*/
sNC.ncFlags = NC_AllowAgg|NC_AllowWin;
sNC.pSrcList = p->pSrc;
sNC.pNext = pOuterNC;
/* Resolve names in the result set. */
if( sqlite3ResolveExprListNames(&sNC, p->pEList) ) return WRC_Abort;
sNC.ncFlags &= ~NC_AllowWin;
/* If there are no aggregate functions in the result-set, and no GROUP BY
** expression, do not allow aggregates in any of the other expressions.
*/
assert( (p->selFlags & SF_Aggregate)==0 );
pGroupBy = p->pGroupBy;
if( pGroupBy || (sNC.ncFlags & NC_HasAgg)!=0 ){
assert( NC_MinMaxAgg==SF_MinMaxAgg );
assert( NC_OrderAgg==SF_OrderByReqd );
p->selFlags |= SF_Aggregate | (sNC.ncFlags&(NC_MinMaxAgg|NC_OrderAgg));
}else{
sNC.ncFlags &= ~NC_AllowAgg;
}
/* Add the output column list to the name-context before parsing the
** other expressions in the SELECT statement. This is so that
** expressions in the WHERE clause (etc.) can refer to expressions by
** aliases in the result set.
**
** Minor point: If this is the case, then the expression will be
** re-evaluated for each reference to it.
*/
assert( (sNC.ncFlags & (NC_UAggInfo|NC_UUpsert|NC_UBaseReg))==0 );
sNC.uNC.pEList = p->pEList;
sNC.ncFlags |= NC_UEList;
if( p->pHaving ){
if( (p->selFlags & SF_Aggregate)==0 ){
sqlite3ErrorMsg(pParse, "HAVING clause on a non-aggregate query");
return WRC_Abort;
}
if( sqlite3ResolveExprNames(&sNC, p->pHaving) ) return WRC_Abort;
}
if( sqlite3ResolveExprNames(&sNC, p->pWhere) ) return WRC_Abort;
/* Resolve names in table-valued-function arguments */
for(i=0; i<p->pSrc->nSrc; i++){
SrcItem *pItem = &p->pSrc->a[i];
if( pItem->fg.isTabFunc
&& sqlite3ResolveExprListNames(&sNC, pItem->u1.pFuncArg)
){
return WRC_Abort;
}
}
#ifndef SQLITE_OMIT_WINDOWFUNC
if( IN_RENAME_OBJECT ){
Window *pWin;
for(pWin=p->pWinDefn; pWin; pWin=pWin->pNextWin){
if( sqlite3ResolveExprListNames(&sNC, pWin->pOrderBy)
|| sqlite3ResolveExprListNames(&sNC, pWin->pPartition)
){
return WRC_Abort;
}
}
}
#endif
/* The ORDER BY and GROUP BY clauses may not refer to terms in
** outer queries
*/
sNC.pNext = 0;
sNC.ncFlags |= NC_AllowAgg|NC_AllowWin;
/* If this is a converted compound query, move the ORDER BY clause from
** the sub-query back to the parent query. At this point each term
** within the ORDER BY clause has been transformed to an integer value.
** These integers will be replaced by copies of the corresponding result
** set expressions by the call to resolveOrderGroupBy() below. */
if( p->selFlags & SF_Converted ){
Select *pSub = p->pSrc->a[0].pSelect;
p->pOrderBy = pSub->pOrderBy;
pSub->pOrderBy = 0;
}
/* Process the ORDER BY clause for singleton SELECT statements.
** The ORDER BY clause for compounds SELECT statements is handled
** below, after all of the result-sets for all of the elements of
** the compound have been resolved.
**
** If there is an ORDER BY clause on a term of a compound-select other
** than the right-most term, then that is a syntax error. But the error
** is not detected until much later, and so we need to go ahead and
** resolve those symbols on the incorrect ORDER BY for consistency.
*/
if( p->pOrderBy!=0
&& isCompound<=nCompound /* Defer right-most ORDER BY of a compound */
&& resolveOrderGroupBy(&sNC, p, p->pOrderBy, "ORDER")
){
return WRC_Abort;
}
if( db->mallocFailed ){
return WRC_Abort;
}
sNC.ncFlags &= ~NC_AllowWin;
/* Resolve the GROUP BY clause. At the same time, make sure
** the GROUP BY clause does not contain aggregate functions.
*/
if( pGroupBy ){
struct ExprList_item *pItem;
if( resolveOrderGroupBy(&sNC, p, pGroupBy, "GROUP") || db->mallocFailed ){
return WRC_Abort;
}
for(i=0, pItem=pGroupBy->a; i<pGroupBy->nExpr; i++, pItem++){
if( ExprHasProperty(pItem->pExpr, EP_Agg) ){
sqlite3ErrorMsg(pParse, "aggregate functions are not allowed in "
"the GROUP BY clause");
return WRC_Abort;
}
}
}
/* If this is part of a compound SELECT, check that it has the right
** number of expressions in the select list. */
if( p->pNext && p->pEList->nExpr!=p->pNext->pEList->nExpr ){
sqlite3SelectWrongNumTermsError(pParse, p->pNext);
return WRC_Abort;
}
/* Advance to the next term of the compound
*/
p = p->pPrior;
nCompound++;
}
/* Resolve the ORDER BY on a compound SELECT after all terms of
** the compound have been resolved.
*/
if( isCompound && resolveCompoundOrderBy(pParse, pLeftmost) ){
return WRC_Abort;
}
return WRC_Prune;
}
/*
** This routine walks an expression tree and resolves references to
** table columns and result-set columns. At the same time, do error
** checking on function usage and set a flag if any aggregate functions
** are seen.
**
** To resolve table columns references we look for nodes (or subtrees) of the
** form X.Y.Z or Y.Z or just Z where
**
** X: The name of a database. Ex: "main" or "temp" or
** the symbolic name assigned to an ATTACH-ed database.
**
** Y: The name of a table in a FROM clause. Or in a trigger
** one of the special names "old" or "new".
**
** Z: The name of a column in table Y.
**
** The node at the root of the subtree is modified as follows:
**
** Expr.op Changed to TK_COLUMN
** Expr.pTab Points to the Table object for X.Y
** Expr.iColumn The column index in X.Y. -1 for the rowid.
** Expr.iTable The VDBE cursor number for X.Y
**
**
** To resolve result-set references, look for expression nodes of the
** form Z (with no X and Y prefix) where the Z matches the right-hand
** size of an AS clause in the result-set of a SELECT. The Z expression
** is replaced by a copy of the left-hand side of the result-set expression.
** Table-name and function resolution occurs on the substituted expression
** tree. For example, in:
**
** SELECT a+b AS x, c+d AS y FROM t1 ORDER BY x;
**
** The "x" term of the order by is replaced by "a+b" to render:
**
** SELECT a+b AS x, c+d AS y FROM t1 ORDER BY a+b;
**
** Function calls are checked to make sure that the function is
** defined and that the correct number of arguments are specified.
** If the function is an aggregate function, then the NC_HasAgg flag is
** set and the opcode is changed from TK_FUNCTION to TK_AGG_FUNCTION.
** If an expression contains aggregate functions then the EP_Agg
** property on the expression is set.
**
** An error message is left in pParse if anything is amiss. The number
** if errors is returned.
*/
int sqlite3ResolveExprNames(
NameContext *pNC, /* Namespace to resolve expressions in. */
Expr *pExpr /* The expression to be analyzed. */
){
int savedHasAgg;
Walker w;
if( pExpr==0 ) return SQLITE_OK;
savedHasAgg = pNC->ncFlags & (NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
w.pParse = pNC->pParse;
w.xExprCallback = resolveExprStep;
w.xSelectCallback = (pNC->ncFlags & NC_NoSelect) ? 0 : resolveSelectStep;
w.xSelectCallback2 = 0;
w.u.pNC = pNC;
#if SQLITE_MAX_EXPR_DEPTH>0
w.pParse->nHeight += pExpr->nHeight;
if( sqlite3ExprCheckHeight(w.pParse, w.pParse->nHeight) ){
return SQLITE_ERROR;
}
#endif
assert( pExpr!=0 );
sqlite3WalkExprNN(&w, pExpr);
#if SQLITE_MAX_EXPR_DEPTH>0
w.pParse->nHeight -= pExpr->nHeight;
#endif
assert( EP_Agg==NC_HasAgg );
assert( EP_Win==NC_HasWin );
testcase( pNC->ncFlags & NC_HasAgg );
testcase( pNC->ncFlags & NC_HasWin );
ExprSetProperty(pExpr, pNC->ncFlags & (NC_HasAgg|NC_HasWin) );
pNC->ncFlags |= savedHasAgg;
return pNC->nNcErr>0 || w.pParse->nErr>0;
}
/*
** Resolve all names for all expression in an expression list. This is
** just like sqlite3ResolveExprNames() except that it works for an expression
** list rather than a single expression.
*/
int sqlite3ResolveExprListNames(
NameContext *pNC, /* Namespace to resolve expressions in. */
ExprList *pList /* The expression list to be analyzed. */
){
int i;
int savedHasAgg = 0;
Walker w;
if( pList==0 ) return WRC_Continue;
w.pParse = pNC->pParse;
w.xExprCallback = resolveExprStep;
w.xSelectCallback = resolveSelectStep;
w.xSelectCallback2 = 0;
w.u.pNC = pNC;
savedHasAgg = pNC->ncFlags & (NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
for(i=0; i<pList->nExpr; i++){
Expr *pExpr = pList->a[i].pExpr;
if( pExpr==0 ) continue;
#if SQLITE_MAX_EXPR_DEPTH>0
w.pParse->nHeight += pExpr->nHeight;
if( sqlite3ExprCheckHeight(w.pParse, w.pParse->nHeight) ){
return WRC_Abort;
}
#endif
sqlite3WalkExprNN(&w, pExpr);
#if SQLITE_MAX_EXPR_DEPTH>0
w.pParse->nHeight -= pExpr->nHeight;
#endif
assert( EP_Agg==NC_HasAgg );
assert( EP_Win==NC_HasWin );
testcase( pNC->ncFlags & NC_HasAgg );
testcase( pNC->ncFlags & NC_HasWin );
if( pNC->ncFlags & (NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg) ){
ExprSetProperty(pExpr, pNC->ncFlags & (NC_HasAgg|NC_HasWin) );
savedHasAgg |= pNC->ncFlags &
(NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
pNC->ncFlags &= ~(NC_HasAgg|NC_MinMaxAgg|NC_HasWin|NC_OrderAgg);
}
if( w.pParse->nErr>0 ) return WRC_Abort;
}
pNC->ncFlags |= savedHasAgg;
return WRC_Continue;
}
/*
** Resolve all names in all expressions of a SELECT and in all
** descendants of the SELECT, including compounds off of p->pPrior,
** subqueries in expressions, and subqueries used as FROM clause
** terms.
**
** See sqlite3ResolveExprNames() for a description of the kinds of
** transformations that occur.
**
** All SELECT statements should have been expanded using
** sqlite3SelectExpand() prior to invoking this routine.
*/
void sqlite3ResolveSelectNames(
Parse *pParse, /* The parser context */
Select *p, /* The SELECT statement being coded. */
NameContext *pOuterNC /* Name context for parent SELECT statement */
){
Walker w;
assert( p!=0 );
w.xExprCallback = resolveExprStep;
w.xSelectCallback = resolveSelectStep;
w.xSelectCallback2 = 0;
w.pParse = pParse;
w.u.pNC = pOuterNC;
sqlite3WalkSelect(&w, p);
}
/*
** Resolve names in expressions that can only reference a single table
** or which cannot reference any tables at all. Examples:
**
** "type" flag
** ------------
** (1) CHECK constraints NC_IsCheck
** (2) WHERE clauses on partial indices NC_PartIdx
** (3) Expressions in indexes on expressions NC_IdxExpr
** (4) Expression arguments to VACUUM INTO. 0
** (5) GENERATED ALWAYS as expressions NC_GenCol
**
** In all cases except (4), the Expr.iTable value for Expr.op==TK_COLUMN
** nodes of the expression is set to -1 and the Expr.iColumn value is
** set to the column number. In case (4), TK_COLUMN nodes cause an error.
**
** Any errors cause an error message to be set in pParse.
*/
int sqlite3ResolveSelfReference(
Parse *pParse, /* Parsing context */
Table *pTab, /* The table being referenced, or NULL */
int type, /* NC_IsCheck, NC_PartIdx, NC_IdxExpr, NC_GenCol, or 0 */
Expr *pExpr, /* Expression to resolve. May be NULL. */
ExprList *pList /* Expression list to resolve. May be NULL. */
){
SrcList sSrc; /* Fake SrcList for pParse->pNewTable */
NameContext sNC; /* Name context for pParse->pNewTable */
int rc;
assert( type==0 || pTab!=0 );
assert( type==NC_IsCheck || type==NC_PartIdx || type==NC_IdxExpr
|| type==NC_GenCol || pTab==0 );
memset(&sNC, 0, sizeof(sNC));
memset(&sSrc, 0, sizeof(sSrc));
if( pTab ){
sSrc.nSrc = 1;
sSrc.a[0].zName = pTab->zName;
sSrc.a[0].pTab = pTab;
sSrc.a[0].iCursor = -1;
if( pTab->pSchema!=pParse->db->aDb[1].pSchema ){
/* Cause EP_FromDDL to be set on TK_FUNCTION nodes of non-TEMP
** schema elements */
type |= NC_FromDDL;
}
}
sNC.pParse = pParse;
sNC.pSrcList = &sSrc;
sNC.ncFlags = type | NC_IsDDL;
if( (rc = sqlite3ResolveExprNames(&sNC, pExpr))!=SQLITE_OK ) return rc;
if( pList ) rc = sqlite3ResolveExprListNames(&sNC, pList);
return rc;
}