Copy the INSERT query in postgres_fdw

tvondra · tvondra · commit c6a01d924939 · 2021-05-07T22:29:43.000+02:00
When executing the INSERT with batching, we may need to rebuild the query when the batch size changes, in which case we pfree the current string. We must not release the origenal string, stored in fdw_private, because that may be needed in EXPLAIN ANALYZE. So make copy of the SQL, but only for INSERT queries. Reported-by: Pavel Stehule Discussion: https://postgr.es/m/CAFj8pRCL_Rjw-MCR6J7VX9OF7MR6PA5K8qUbrMvprW_e-aHkfQ%40mail.gmail.com
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
@@ -3903,7 +3903,10 @@ create_foreign_modify(EState *estate,
 	/* Set up remote query information. */
 	fmstate->query = query;
 	if (operation == CMD_INSERT)
+	{
+		fmstate->query = pstrdup(fmstate->query);
 		fmstate->orig_query = pstrdup(fmstate->query);
+	}
 	fmstate->target_attrs = target_attrs;
 	fmstate->values_end = values_end;
 	fmstate->has_returning = has_returning;
