From: PG Bug reporting form <noreply@postgresql.org>
To: pgsql-bugs@lists.postgresql.org
Cc: zengman@halodbtech.com
Subject: BUG #18710: "pg_get_viewdef" triggers assertions in special scenarios
Date: Fri, 15 Nov 2024 02:50:47 +0000
Message-ID: <18710-ceab935c95da55aa@postgresql.org> (raw)
The following bug has been logged on the website:
Bug reference: 18710
Logged by: Man Zeng
Email address: zengman@halodbtech.com
PostgreSQL version: 14.14
Operating system: centos-8
Description:
A prototype of the problem from
https://github.com/duckdb/pg_duckdb/issues/435
This exception can be reliably triggered by calling "pg_get_viewdef"
Step 1 ：
CREATE VIEW view_a AS
WITH RECURSIVE outermost(x) AS (
SELECT 1
UNION (WITH innermost1 AS (
SELECT 2)
SELECT * FROM outermost
UNION SELECT * FROM innermost1)
)
SELECT * FROM outermost ORDER BY 1;
Step 2 ：
SELECT oid FROM pg_class where relname = 'view_a';
Step 3：
SELECT pg_get_viewdef( this oid ); -- error
The abnormalities appear as follows
[postgres@iZuf6hwo0wgeev4dvua4csZ postgres]$ psql
psql (14.14)
Type "help" for help.
postgres=# CREATE VIEW view_a AS
postgres-# WITH RECURSIVE outermost(x) AS (
postgres(# SELECT 1
postgres(# UNION (WITH innermost1 AS (
postgres(# SELECT 2)
postgres(# SELECT * FROM outermost
postgres(# UNION SELECT * FROM innermost1)
postgres(# )
postgres-# SELECT * FROM outermost ORDER BY 1;
CREATE VIEW
postgres=# SELECT * FROM pg_class where relname = 'view_a';
oid | relname | relnamespace | reltype | reloftype | relowner | relam |
relfilenode | reltablespace | relpages | reltuples | relallvisible |
reltoastrelid | relhasindex | relisshared | relpersistence | relkind |
relnatt
s | relchecks | relhasrules | relhastriggers | relhassubclass |
relrowsecurity | relforcerowsecurity | relispopulated | relreplident |
relispartition | relrewrite | relfrozenxid | relminmxid | relacl |
reloptions | relpart
bound
-------+---------+--------------+---------+-----------+----------+-------+-------------+---------------+----------+-----------+---------------+---------------+-------------+-------------+----------------+---------+--------
--+-----------+-------------+----------------+----------------+----------------+---------------------+----------------+--------------+----------------+------------+--------------+------------+--------+------------+--------
------
32768 | view_a | 2200 | 32770 | 0 | 10 | 0 |
0 | 0 | 0 | -1 | 0 |
0 | f | f | p | v |
1 | 0 | t | f | f | f
| f | t | n | f |
0 | 0 | 0 | | |
(1 row)
postgres=# select pg_get_viewdef(32768);
TRAP: FailedAssertion("subquery->setOperations == NULL", File:
"ruleutils.c", Line: 6094, PID: 325948)
postgres: postgres postgres [local]
SELECT(ExceptionalCondition+0xb9)[0xb1a6c1]
postgres: postgres postgres [local] SELECT[0xa95d6b]
postgres: postgres postgres [local] SELECT[0xa960b5]
......
Maybe we can comment out the assertion that raises the exception, because I
looked up the code and found that the assertion doesn't seem to make a lot
of sense here.
I look forward to your discussion.
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-bugs@postgresql.org
Cc: noreply@postgresql.org, pgsql-bugs@lists.postgresql.org, zengman@halodbtech.com
Subject: Re: BUG #18710: "pg_get_viewdef" triggers assertions in special scenarios
In-Reply-To: <18710-ceab935c95da55aa@postgresql.org>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox