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Disable the push-down optimization for sub-queries that are INTERSECT, UNION or EXCEPT compounds. dbsqlfuzz a34f455c91ad75a0cf8cd9476841903f42930a7a.

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FossilOrigin-Name: 346a3b12b861ce7ba369e98cd336f79a1d4f7a7bb9acd7a4f63f37b391755bf5
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dan
2022-10-26 21:14:21 +00:00
parent 07dd481010
commit 195687f1bf
4 changed files with 44 additions and 9 deletions
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11
src/select.c
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@@ -5009,6 +5009,13 @@ static int pushDownWindowCheck(Parse *pParse, Select *pSubq, Expr *pExpr){
** be materialized. (This restriction is implemented in the calling
** routine.)
**
** (8) The subquery may not be a compound that uses UNION, INTERSECT,
** or EXCEPT. (We could, perhaps, relax this restriction to allow
** this case if none of the comparisons operators between left and
** right arms of the compound use a collation other than BINARY.
** But it is a lot of work to check that case for an obscure and
** minor optimization, so we omit it for now.)
**
** Return 0 if no changes are made and non-zero if one or more WHERE clause
** terms are duplicated into the subquery.
*/
@@ -5028,6 +5035,10 @@ static int pushDownWhereTerms(
if( pSubq->pPrior ){
Select *pSel;
for(pSel=pSubq; pSel; pSel=pSel->pPrior){
u8 op = pSel->op;
assert( op==TK_ALL || op==TK_SELECT
|| op==TK_UNION || op==TK_INTERSECT || op==TK_EXCEPT );
if( op!=TK_ALL && op!=TK_SELECT ) return 0; /* restriction (8) */
if( pSel->pWin ) return 0; /* restriction (6b) */
}
}else{