diff --git a/internal/server/expr.go b/internal/server/expr.go
index dc1e75f3..dd03d158 100644
--- a/internal/server/expr.go
+++ b/internal/server/expr.go
@@ -91,6 +91,7 @@ func newExprPool(s *Server) *exprPool {
 						return resultToValue(r), nil
 					}
 				}
+				return expr.Number(0), nil
 			} else {
 				switch v := info.Value.Value().(type) {
 				case gjson.Result:
@@ -102,8 +103,8 @@ func newExprPool(s *Server) *exprPool {
 						return expr.Function("match"), nil
 					}
 				}
+				return expr.Undefined, nil
 			}
-			return expr.Undefined, nil
 		},
 		// call
 		func(info expr.CallInfo, ctx *expr.Context) (expr.Value, error) {
diff --git a/tests/keys_test.go b/tests/keys_test.go
index 759c0077..1b14329d 100644
--- a/tests/keys_test.go
+++ b/tests/keys_test.go
@@ -600,6 +600,17 @@ func keys_FIELDS_test(mc *mockServer) error {
 		Do("SCAN", "fleet", "WHERE", "props.speed > 53", "IDS").JSON().Str(`{"ok":true,"ids":[],"count":0,"cursor":0}`),
 		Do("SCAN", "fleet", "WHERE", "Props.speed > 53", "IDS").JSON().Str(`{"ok":true,"ids":[],"count":0,"cursor":0}`),
 		Do("SCAN", "fleet", "WHERE", "Props.Speed > 53", "IDS").JSON().Str(`{"ok":true,"ids":[],"count":0,"cursor":0}`),
+
+		Do("DROP", "fleet").JSON().OK(),
+		Do("SET", "fleet", "1", "field", "teamId", "1", "field", "optionalId", "999", "point", "0", "0").JSON().OK(),
+		Do("SET", "fleet", "2", "field", "teamId", "1", "point", "0", "0").JSON().OK(),
+		Do("SCAN", "fleet", "COUNT").JSON().Str(`{"ok":true,"count":2,"cursor":0}`),
+		Do("SCAN", "fleet", "WHEREIN", "teamId", "1", "1", "COUNT").JSON().Str(`{"ok":true,"count":2,"cursor":0}`),
+
+		Do("SCAN", "fleet", "WHEREIN", "teamId", "1", "1", "WHERE", "!optionalId || optionalId == 999", "count").JSON().Str(`{"ok":true,"count":2,"cursor":0}`),
+		Do("SCAN", "fleet", "WHEREIN", "teamId", "1", "1", "WHERE", "!!!optionalId || optionalId == 999", "count").JSON().Str(`{"ok":true,"count":2,"cursor":0}`),
+		Do("SCAN", "fleet", "WHEREIN", "teamId", "1", "1", "WHERE", "optionalId == 0 || optionalId == 999", "count").JSON().Str(`{"ok":true,"count":2,"cursor":0}`),
+		Do("SCAN", "fleet", "WHEREIN", "teamId", "1", "1", "WHERE", "1 == 1 || optionalId == 999", "count").JSON().Str(`{"ok":true,"count":2,"cursor":0}`),
 	)
 }