Re: Dynamic constraint names in ALTER TABLE

On Monday, September 19, 2011 5:10:45 pm patrick keshishian wrote:
> Hi,
>

>
>
> Is there any way the .sql scripts could make use of this query to get
> the foreign key name from pg_constraint table, regardless of PG
> version (7.4.x or 9.x)?

Use the information schema? As example:
http://www.postgresql.org/docs/7.4/static/infoschema-table-constraints.html
http://www.postgresql.org/docs/9.0/interactive/infoschema-table-constraints.html

>
> foo=# SELECT conname FROM pg_constraint JOIN pg_class ON
> (conrelid=pg_class.oid) WHERE pg_class.relname='sales' AND conkey[1] =
> 1 AND contype='f';
>
> In PostgreSQL 7.4.17:
> conname
> ---------
> $1
> (1 row)
>
>
> In PostgreSQL 9.0.3:
> conname
> -------------------
> sales_seller_fkey
> (1 row)
>
>
> Thanks for reading,
> --patrick

--
Adrian Klaver
adrian(dot)klaver(at)gmail(dot)com