Back out the EXISTS-to-IN optimization. It slows things down rather than

speeds them up depending on the query.  And (see
[forum:/forumpost/8692d94725|forum post 8692d94725]) it sometimes results in
an incorrect answer.  We may come back and revisit this optimization later,
but for now it seems best just to disable it.

FossilOrigin-Name: 16252d73fa73569fd7506676f6ffbbcd43addfb105384fb74449d30ca720904a

1 files changed, 1 insertions, 12 deletions

diff --git a/src/expr.c b/src/expr.c
index 140260931..7a2df30fd 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -95,18 +95,7 @@ Expr *sqlite3ExprAddCollateToken(
   const Token *pCollName,  /* Name of collating sequence */
   int dequote              /* True to dequote pCollName */
 ){
-  assert( pExpr!=0 || pParse->db->mallocFailed );
-  if( pExpr==0 ) return 0;
-  if( pExpr->op==TK_VECTOR ){
-    ExprList *pList = pExpr->x.pList;
-    if( ALWAYS(pList!=0) ){
-      int i;
-      for(i=0; i<pList->nExpr; i++){
-        pList->a[i].pExpr = sqlite3ExprAddCollateToken(pParse,pList->a[i].pExpr,
-                                                       pCollName, dequote);
-      }
-    }
-  }else if( pCollName->n>0 ){
+  if( pCollName->n>0 ){
     Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLLATE, pCollName, dequote);
     if( pNew ){
       pNew->pLeft = pExpr;