raise warning when record type cannot be detected

Author: okbob

expected/plpgsql_check_active.out

@@ -3841,6 +3841,29 @@ select * from plpgsql_check_function('dyn_sql_3');
  Context: SQL statement "SELECT r.c"
 (2 rows)
 
+drop function dyn_sql_3();
+create or replace function dyn_sql_3()
+returns void as $$
+declare
+  r record;
+  v text = 'select 10 a, 20 b't;
+begin
+  select 10 a, 20 b into r;
+  for r in execute v
+  loop
+    raise notice '%', r.a;
+  end loop;
+end
+$$ language plpgsql;
+-- should be warning
+select * from plpgsql_check_function('dyn_sql_3');
+                                plpgsql_check_function                                 
+---------------------------------------------------------------------------------------
+ warning:00000:7:FOR over EXECUTE statement:cannot determinate a result of dynamic SQL
+ Detail: There is a risk of related false alarms.
+ Hint: Don't use dynamic SQL and record type together, when you would check function.
+(3 rows)
+
 drop function dyn_sql_3();
 create or replace function dyn_sql_4()
 returns table(ax int, bx int) as $$

sql/plpgsql_check_active.sql

@@ -2800,6 +2800,25 @@ select * from plpgsql_check_function('dyn_sql_3');
 
 drop function dyn_sql_3();
 
+create or replace function dyn_sql_3()
+returns void as $$
+declare
+  r record;
+  v text = 'select 10 a, 20 b't;
+begin
+  select 10 a, 20 b into r;
+  for r in execute v
+  loop
+    raise notice '%', r.a;
+  end loop;
+end
+$$ language plpgsql;
+
+-- should be warning
+select * from plpgsql_check_function('dyn_sql_3');
+
+drop function dyn_sql_3();
+
 create or replace function dyn_sql_4()
 returns table(ax int, bx int) as $$
 begin

src/stmtwalk.c

@@ -1774,6 +1774,7 @@ check_dynamic_sql(PLpgSQL_checkstate *cstate,
 	Node	   *expr_node;
 	ListCell   *l;
 	int			loc = -1;
+	bool		raise_unknown_rec_warning = false;
 
 	/*
 	 * possible checks:
@@ -1903,6 +1904,27 @@ check_dynamic_sql(PLpgSQL_checkstate *cstate,
 									query->query,
 									NULL);
 		}
+
+		/*
+		 * In this case, we don't know a result type, and we should
+		 * to raise warning about this situation.
+		 */
+		if (into)
+		{
+
+#if PG_VERSION_NUM >= 110000
+
+			if (target->dtype == PLPGSQL_DTYPE_REC)
+				raise_unknown_rec_warning = true;
+
+#else
+
+			if (rec)
+				raise_unknown_rec_warning = true;
+
+#endif
+
+		}
 	}
 
 	/* recheck if target rec var has assigned tupdesc */
@@ -1913,22 +1935,23 @@ check_dynamic_sql(PLpgSQL_checkstate *cstate,
 
 		check_variable(cstate, target);
 
-		if (target->dtype == PLPGSQL_DTYPE_REC &&
-			!has_assigned_tupdesc(cstate, (PLpgSQL_rec *) target))
+		if (raise_unknown_rec_warning ||
+			(target->dtype == PLPGSQL_DTYPE_REC &&
+			 !has_assigned_tupdesc(cstate, (PLpgSQL_rec *) target)))
 
 #else
 
 		plpgsql_check_row_or_rec(cstate, row, rec);
 
-		if (rec != NULL && !has_assigned_tupdesc(cstate, rec))
+		if (raise_unknown_rec_warning || (rec != NULL && !has_assigned_tupdesc(cstate, rec)))
 
 #endif
 
 		{
 			plpgsql_check_put_error(cstate,
 									0, 0,
 									"cannot determinate a result of dynamic SQL",
-									"Cannot to contine in check.",
+									"There is a risk of related false alarms.",
 						  "Don't use dynamic SQL and record type together, when you would check function.",
 									PLPGSQL_CHECK_WARNING_OTHERS,
 									0, NULL, NULL);