diff --git a/executor.go b/executor.go
index b39e26f58..9b7f5d4bb 100644
--- a/executor.go
+++ b/executor.go
@@ -1577,7 +1577,7 @@ func (e *executor) translateCall(index string, idx *Index, c *pql.Call) error {
 		if field == nil {
 			return ErrFieldNotFound
 		}
-		if field.Keys() {
+		if field.keys() {
 			if c.Args[rowKey] != nil && !isString(c.Args[rowKey]) {
 				return errors.New("row value must be a string when field 'keys' option enabled")
 			}
@@ -1628,7 +1628,7 @@ func (e *executor) translateResult(index string, idx *Index, call *pql.Call, res
 			if field == nil {
 				return nil, ErrFieldNotFound
 			}
-			if field.Keys() {
+			if field.keys() {
 				other := make([]Pair, len(result))
 				for i := range result {
 					key, err := e.TranslateStore.TranslateRowToString(index, fieldName, result[i].ID)
diff --git a/field.go b/field.go
index b9d84cc83..69d08d504 100644
--- a/field.go
+++ b/field.go
@@ -428,8 +428,8 @@ func (f *Field) Close() error {
 	return nil
 }
 
-// Keys returns true if the field uses string keys.
-func (f *Field) Keys() bool {
+// keys returns true if the field uses string keys.
+func (f *Field) keys() bool {
 	f.mu.RLock()
 	defer f.mu.RUnlock()
 	return f.options.Keys