1 files changed, 14 insertions, 0 deletions
diff --git a/src/where.c b/src/where.c
index 05ae24f7b..448fe27c1 100644
--- a/src/where.c
+++ b/src/where.c
@@ -5810,6 +5810,20 @@ static SQLITE_NOINLINE void whereAddIndexedExpr(
       continue;
     }
     if( sqlite3ExprIsConstant(pExpr) ) continue;
+    if( pExpr->op==TK_FUNCTION ){
+      /* Functions that might set a subtype should not be replaced by the
+      ** value taken from an expression index since the index omits the
+      ** subtype.  https://sqlite.org/forum/forumpost/68d284c86b082c3e */
+      int n;
+      FuncDef *pDef;
+      sqlite3 *db = pParse->db;
+      assert( ExprUseXList(pExpr) );
+      n = pExpr->x.pList ? pExpr->x.pList->nExpr : 0;
+      pDef = sqlite3FindFunction(db, pExpr->u.zToken, n, ENC(db), 0);
+      if( NEVER(pDef==0) || (pDef->funcFlags & SQLITE_RESULT_SUBTYPE)!=0 ){
+        continue;
+      }
+    }
     p = sqlite3DbMallocRaw(pParse->db,  sizeof(IndexedExpr));
     if( p==0 ) break;
     p->pIENext = pParse->pIdxEpr;