Re: TRUNCATE TABLE corrupts pg_class.relfilenode = pg_attrdef.pg_attrdef

We will test with 9.6.3 too.

Seb

On 05/22/2017 12:51 PM, Sebastien FLAESCH wrote:
> Hi all,
>
> Testing with Postgresql 9.6rc1 (but also detected with prior versions):
>
> It is normal that a TRUNCATE TABLE statement changes the table/sequence relation in pg_attrdef?
>
> test1=> create table mytab ( pkey serial, name varchar(10) );
> test1=> select a.adsrc from pg_class p join pg_attrdef a on (p.relfilenode = a.adrelid) where lower(p.relname) = lower('mytab');
> adsrc
> -------------------------------------
> nextval('mytab_pkey_seq'::regclass)
> (1 row)
>
> test1=> truncate table mytab;
> TRUNCATE TABLE
> test1=> select a.adsrc from pg_class p join pg_attrdef a on (p.relfilenode = a.adrelid) where lower(p.relname) = lower('mytab');
> adsrc
> -------
> (0 rows)
>
> test1=> select adrelid, adsrc from pg_attrdef where adsrc like '%mytab%';
> adrelid | adsrc
> ---------+-------------------------------------
> 6904163 | nextval('mytab_pkey_seq'::regclass)
> (1 row)
>
>
> Are we mis-using the condition (p.relfilenode = a.adrelid) in the first SELECT?
>
> How can we easily check if a table is defined with a SERIAL type?
>
> Thanks!
> Seb
>
>