diff --git a/digdag-docs/src/operators/pg.md b/digdag-docs/src/operators/pg.md
index 20613d3542..b6f3101e73 100644
--- a/digdag-docs/src/operators/pg.md
+++ b/digdag-docs/src/operators/pg.md
@@ -90,7 +90,7 @@ _export:
   download_file: output.csv
   ```
 
-* **store_last_results**: first | all
+* **store_last_results**: false | first | all
 
   Whether to store the query results to ``pg.last_results`` parameter. *Default:* `false`.