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-rw-r--r--src/select.c139
1 files changed, 96 insertions, 43 deletions
diff --git a/src/select.c b/src/select.c
index a90877dc6..316889480 100644
--- a/src/select.c
+++ b/src/select.c
@@ -55,7 +55,7 @@ Select *sqlite3SelectNew(
ExprList *pGroupBy, /* the GROUP BY clause */
Expr *pHaving, /* the HAVING clause */
ExprList *pOrderBy, /* the ORDER BY clause */
- int isDistinct, /* true if the DISTINCT keyword is present */
+ u16 selFlags, /* Flag parameters, such as SF_Distinct */
Expr *pLimit, /* LIMIT value. NULL means not used */
Expr *pOffset /* OFFSET value. NULL means no offset */
){
@@ -79,7 +79,7 @@ Select *sqlite3SelectNew(
pNew->pGroupBy = pGroupBy;
pNew->pHaving = pHaving;
pNew->pOrderBy = pOrderBy;
- pNew->selFlags = isDistinct ? SF_Distinct : 0;
+ pNew->selFlags = selFlags;
pNew->op = TK_SELECT;
pNew->pLimit = pLimit;
pNew->pOffset = pOffset;
@@ -1336,8 +1336,6 @@ static int selectColumnsFromExprList(
/* Get an appropriate name for the column
*/
p = sqlite3ExprSkipCollate(pEList->a[i].pExpr);
- assert( p->pRight==0 || ExprHasProperty(p->pRight, EP_IntValue)
- || p->pRight->u.zToken==0 || p->pRight->u.zToken[0]!=0 );
if( (zName = pEList->a[i].zName)!=0 ){
/* If the column contains an "AS <name>" phrase, use <name> as the name */
zName = sqlite3DbStrDup(db, zName);
@@ -1375,6 +1373,9 @@ static int selectColumnsFromExprList(
for(j=cnt=0; j<i; j++){
if( sqlite3StrICmp(aCol[j].zName, zName)==0 ){
char *zNewName;
+ int k;
+ for(k=nName-1; k>1 && sqlite3Isdigit(zName[k]); k--){}
+ if( zName[k]==':' ) nName = k;
zName[nName] = 0;
zNewName = sqlite3MPrintf(db, "%s:%d", zName, ++cnt);
sqlite3DbFree(db, zName);
@@ -3160,34 +3161,43 @@ static int flattenSubquery(
#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */
/*
-** Analyze the SELECT statement passed as an argument to see if it
-** is a min() or max() query. Return WHERE_ORDERBY_MIN or WHERE_ORDERBY_MAX if
-** it is, or 0 otherwise. At present, a query is considered to be
-** a min()/max() query if:
+** Based on the contents of the AggInfo structure indicated by the first
+** argument, this function checks if the following are true:
**
-** 1. There is a single object in the FROM clause.
+** * the query contains just a single aggregate function,
+** * the aggregate function is either min() or max(), and
+** * the argument to the aggregate function is a column value.
**
-** 2. There is a single expression in the result set, and it is
-** either min(x) or max(x), where x is a column reference.
+** If all of the above are true, then WHERE_ORDERBY_MIN or WHERE_ORDERBY_MAX
+** is returned as appropriate. Also, *ppMinMax is set to point to the
+** list of arguments passed to the aggregate before returning.
+**
+** Or, if the conditions above are not met, *ppMinMax is set to 0 and
+** WHERE_ORDERBY_NORMAL is returned.
*/
-static u8 minMaxQuery(Select *p){
- Expr *pExpr;
- ExprList *pEList = p->pEList;
-
- if( pEList->nExpr!=1 ) return WHERE_ORDERBY_NORMAL;
- pExpr = pEList->a[0].pExpr;
- if( pExpr->op!=TK_AGG_FUNCTION ) return 0;
- if( NEVER(ExprHasProperty(pExpr, EP_xIsSelect)) ) return 0;
- pEList = pExpr->x.pList;
- if( pEList==0 || pEList->nExpr!=1 ) return 0;
- if( pEList->a[0].pExpr->op!=TK_AGG_COLUMN ) return WHERE_ORDERBY_NORMAL;
- assert( !ExprHasProperty(pExpr, EP_IntValue) );
- if( sqlite3StrICmp(pExpr->u.zToken,"min")==0 ){
- return WHERE_ORDERBY_MIN;
- }else if( sqlite3StrICmp(pExpr->u.zToken,"max")==0 ){
- return WHERE_ORDERBY_MAX;
+static u8 minMaxQuery(AggInfo *pAggInfo, ExprList **ppMinMax){
+ int eRet = WHERE_ORDERBY_NORMAL; /* Return value */
+
+ *ppMinMax = 0;
+ if( pAggInfo->nFunc==1 ){
+ Expr *pExpr = pAggInfo->aFunc[0].pExpr; /* Aggregate function */
+ ExprList *pEList = pExpr->x.pList; /* Arguments to agg function */
+
+ assert( pExpr->op==TK_AGG_FUNCTION );
+ if( pEList && pEList->nExpr==1 && pEList->a[0].pExpr->op==TK_AGG_COLUMN ){
+ const char *zFunc = pExpr->u.zToken;
+ if( sqlite3StrICmp(zFunc, "min")==0 ){
+ eRet = WHERE_ORDERBY_MIN;
+ *ppMinMax = pEList;
+ }else if( sqlite3StrICmp(zFunc, "max")==0 ){
+ eRet = WHERE_ORDERBY_MAX;
+ *ppMinMax = pEList;
+ }
+ }
}
- return WHERE_ORDERBY_NORMAL;
+
+ assert( *ppMinMax==0 || (*ppMinMax)->nExpr==1 );
+ return eRet;
}
/*
@@ -3282,6 +3292,7 @@ static int selectExpander(Walker *pWalker, Select *p){
ExprList *pEList;
struct SrcList_item *pFrom;
sqlite3 *db = pParse->db;
+ Expr *pE, *pRight, *pExpr;
if( db->mallocFailed ){
return WRC_Abort;
@@ -3367,7 +3378,7 @@ static int selectExpander(Walker *pWalker, Select *p){
** that need expanding.
*/
for(k=0; k<pEList->nExpr; k++){
- Expr *pE = pEList->a[k].pExpr;
+ pE = pEList->a[k].pExpr;
if( pE->op==TK_ALL ) break;
assert( pE->op!=TK_DOT || pE->pRight!=0 );
assert( pE->op!=TK_DOT || (pE->pLeft!=0 && pE->pLeft->op==TK_ID) );
@@ -3385,10 +3396,18 @@ static int selectExpander(Walker *pWalker, Select *p){
int longNames = (flags & SQLITE_FullColNames)!=0
&& (flags & SQLITE_ShortColNames)==0;
+ /* When processing FROM-clause subqueries, it is always the case
+ ** that full_column_names=OFF and short_column_names=ON. The
+ ** sqlite3ResultSetOfSelect() routine makes it so. */
+ assert( (p->selFlags & SF_NestedFrom)==0
+ || ((flags & SQLITE_FullColNames)==0 &&
+ (flags & SQLITE_ShortColNames)!=0) );
+
for(k=0; k<pEList->nExpr; k++){
- Expr *pE = a[k].pExpr;
- assert( pE->op!=TK_DOT || pE->pRight!=0 );
- if( pE->op!=TK_ALL && (pE->op!=TK_DOT || pE->pRight->op!=TK_ALL) ){
+ pE = a[k].pExpr;
+ pRight = pE->pRight;
+ assert( pE->op!=TK_DOT || pRight!=0 );
+ if( pE->op!=TK_ALL && (pE->op!=TK_DOT || pRight->op!=TK_ALL) ){
/* This particular expression does not need to be expanded.
*/
pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr);
@@ -3403,32 +3422,43 @@ static int selectExpander(Walker *pWalker, Select *p){
/* This expression is a "*" or a "TABLE.*" and needs to be
** expanded. */
int tableSeen = 0; /* Set to 1 when TABLE matches */
- char *zTName; /* text of name of TABLE */
+ char *zTName = 0; /* text of name of TABLE */
if( pE->op==TK_DOT ){
assert( pE->pLeft!=0 );
assert( !ExprHasProperty(pE->pLeft, EP_IntValue) );
zTName = pE->pLeft->u.zToken;
- }else{
- zTName = 0;
}
for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
Table *pTab = pFrom->pTab;
+ Select *pSub = pFrom->pSelect;
char *zTabName = pFrom->zAlias;
+ const char *zSchemaName = 0;
+ int iDb;
if( zTabName==0 ){
zTabName = pTab->zName;
}
if( db->mallocFailed ) break;
- if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){
- continue;
+ if( pSub==0 || (pSub->selFlags & SF_NestedFrom)==0 ){
+ pSub = 0;
+ if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){
+ continue;
+ }
+ iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+ zSchemaName = iDb>=0 ? db->aDb[iDb].zName : "*";
}
- tableSeen = 1;
for(j=0; j<pTab->nCol; j++){
- Expr *pExpr, *pRight;
char *zName = pTab->aCol[j].zName;
char *zColname; /* The computed column name */
char *zToFree; /* Malloced string that needs to be freed */
Token sColname; /* Computed column name as a token */
+ assert( zName );
+ if( zTName && pSub
+ && sqlite3MatchSpanName(pSub->pEList->a[j].zSpan, 0, zTName, 0)==0
+ ){
+ continue;
+ }
+
/* If a column is marked as 'hidden' (currently only possible
** for virtual tables), do not include it in the expanded
** result-set list.
@@ -3437,6 +3467,7 @@ static int selectExpander(Walker *pWalker, Select *p){
assert(IsVirtual(pTab));
continue;
}
+ tableSeen = 1;
if( i>0 && zTName==0 ){
if( (pFrom->jointype & JT_NATURAL)!=0
@@ -3459,6 +3490,10 @@ static int selectExpander(Walker *pWalker, Select *p){
Expr *pLeft;
pLeft = sqlite3Expr(db, TK_ID, zTabName);
pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
+ if( zSchemaName ){
+ pLeft = sqlite3Expr(db, TK_ID, zSchemaName);
+ pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pExpr, 0);
+ }
if( longNames ){
zColname = sqlite3MPrintf(db, "%s.%s", zTabName, zName);
zToFree = zColname;
@@ -3470,6 +3505,18 @@ static int selectExpander(Walker *pWalker, Select *p){
sColname.z = zColname;
sColname.n = sqlite3Strlen30(zColname);
sqlite3ExprListSetName(pParse, pNew, &sColname, 0);
+ if( pNew && (p->selFlags & SF_NestedFrom)!=0 ){
+ struct ExprList_item *pX = &pNew->a[pNew->nExpr-1];
+ if( pSub ){
+ pX->zSpan = sqlite3DbStrDup(db, pSub->pEList->a[j].zSpan);
+ testcase( pX->zSpan==0 );
+ }else{
+ pX->zSpan = sqlite3MPrintf(db, "%s.%s.%s",
+ zSchemaName, zTabName, zColname);
+ testcase( pX->zSpan==0 );
+ }
+ pX->bSpanIsTab = 1;
+ }
sqlite3DbFree(db, zToFree);
}
}
@@ -4527,11 +4574,17 @@ int sqlite3Select(
** Refer to code and comments in where.c for details.
*/
ExprList *pMinMax = 0;
- u8 flag = minMaxQuery(p);
+ u8 flag = WHERE_ORDERBY_NORMAL;
+
+ assert( p->pGroupBy==0 );
+ assert( flag==0 );
+ if( p->pHaving==0 ){
+ flag = minMaxQuery(&sAggInfo, &pMinMax);
+ }
+ assert( flag==0 || (pMinMax!=0 && pMinMax->nExpr==1) );
+
if( flag ){
- assert( !ExprHasProperty(p->pEList->a[0].pExpr, EP_xIsSelect) );
- assert( p->pEList->a[0].pExpr->x.pList->nExpr==1 );
- pMinMax = sqlite3ExprListDup(db, p->pEList->a[0].pExpr->x.pList,0);
+ pMinMax = sqlite3ExprListDup(db, pMinMax, 0);
pDel = pMinMax;
if( pMinMax && !db->mallocFailed ){
pMinMax->a[0].sortOrder = flag!=WHERE_ORDERBY_MIN ?1:0;