[pgpool-general: 6413] Re: Unable to parse the query

[Takuma Hoshiai]

Hi,

On Thu, 14 Feb 2019 18:18:17 +0700
milist ujang <ujang.milist at gmail.com> wrote:

> HI all,
> 
> Recently I'm using version 3.7.5 (amefuriboshi). there are 4 backends
> streaming replication (synchronous), and 1 primary.
> 
> Intermittently user got SQLState: 02000 (No results were returned by the
> query), take a look at pgpool log file, got this error on the same time:
> 
> Unable to parse the query: "select * from (select branch_type as A from
> branch where parent_id in (1701) order by branch_id) limit 1 " from client
> ...

This pgpool log is correct.
its query is wrong.  'FROM' clause using subquery must be assigned a table alias name.

ex.)
  select * from ( select branch_type as A 
    from branch where parent_id in (1701) order by branch_id) AS tmp_tbl limit 1 
                                                              ^^^^^^^^^^
Is a query shown in log the same as query to return 'SQLState: 02000' ?
 
> using the same query at the later time is OK, the table is static one.
Really? if same query is success, maybe it is bug.


> anyway, we use query cache (shmem) and there are a lot of
> LOG:  error while deleting item from shmem cache, item: NNN was already
> deleted
> is this 2 log may be correlated? is it due to high pressure on cache?
> (recently no filter at all in cache)

This log is corrent too. Using query cache offen logged.
 

> 
> -- 
> regards
> 
> ujang jaenudin | DBA Consultant (Freelancer)
> http://ora62.wordpress.com
> http://id.linkedin.com/pub/ujang-jaenudin/12/64/bab


-- 
Takuma Hoshiai <hoshiai at sraoss.co.jp>