Enhance the LIKE/GLOB query optimization so that it works as long as there

is an index with the appropriate collating sequence and even if the default
collating sequence of the column is different.
Ticket [4711020446da7d93d99].

FossilOrigin-Name: 9f932655f9eb9fdab16d7deed98b7cad414e0ca6

1 files changed, 15 insertions, 8 deletions

diff --git a/src/expr.c b/src/expr.c
index 204643316..bd28bf939 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -56,24 +56,31 @@ char sqlite3ExprAffinity(Expr *pExpr){
 }
 
 /*
+** Set the explicit collating sequence for an expression to the
+** collating sequence supplied in the second argument.
+*/
+Expr *sqlite3ExprSetColl(Expr *pExpr, CollSeq *pColl){
+  if( pExpr && pColl ){
+    pExpr->pColl = pColl;
+    pExpr->flags |= EP_ExpCollate;
+  }
+  return pExpr;
+}
+
+/*
 ** Set the collating sequence for expression pExpr to be the collating
 ** sequence named by pToken.   Return a pointer to the revised expression.
 ** The collating sequence is marked as "explicit" using the EP_ExpCollate
 ** flag.  An explicit collating sequence will override implicit
 ** collating sequences.
 */
-Expr *sqlite3ExprSetColl(Parse *pParse, Expr *pExpr, Token *pCollName){
+Expr *sqlite3ExprSetCollByToken(Parse *pParse, Expr *pExpr, Token *pCollName){
   char *zColl = 0;            /* Dequoted name of collation sequence */
   CollSeq *pColl;
   sqlite3 *db = pParse->db;
   zColl = sqlite3NameFromToken(db, pCollName);
-  if( pExpr && zColl ){
-    pColl = sqlite3LocateCollSeq(pParse, zColl);
-    if( pColl ){
-      pExpr->pColl = pColl;
-      pExpr->flags |= EP_ExpCollate;
-    }
-  }
+  pColl = sqlite3LocateCollSeq(pParse, zColl);
+  sqlite3ExprSetColl(pExpr, pColl);
   sqlite3DbFree(db, zColl);
   return pExpr;
 }