diff options
Diffstat (limited to 'sqlglot/optimizer/qualify_columns.py')
| -rw-r--r-- | sqlglot/optimizer/qualify_columns.py | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/sqlglot/optimizer/qualify_columns.py b/sqlglot/optimizer/qualify_columns.py index 7972b2b..2657188 100644 --- a/sqlglot/optimizer/qualify_columns.py +++ b/sqlglot/optimizer/qualify_columns.py @@ -29,12 +29,13 @@ def qualify_columns( 'SELECT tbl.col AS col FROM tbl' Args: - expression: expression to qualify - schema: Database schema - expand_alias_refs: whether or not to expand references to aliases - infer_schema: whether or not to infer the schema if missing + expression: Expression to qualify. + schema: Database schema. + expand_alias_refs: Whether or not to expand references to aliases. + infer_schema: Whether or not to infer the schema if missing. + Returns: - sqlglot.Expression: qualified expression + The qualified expression. """ schema = ensure_schema(schema) infer_schema = schema.empty if infer_schema is None else infer_schema @@ -410,7 +411,9 @@ def _expand_stars( else: return - scope.expression.set("expressions", new_selections) + # Ensures we don't overwrite the initial selections with an empty list + if new_selections: + scope.expression.set("expressions", new_selections) def _add_except_columns( |