Re: Getting the currently used sequence for a SERIAL column

On 2016-10-19 09:28, Thomas Kellerer wrote:
> You can use the following statement to find the sequences that a table uses:
>
> select sn.nspname as sequence_schema, s.relname as sequence_name
> from pg_class s
> join pg_namespace sn on sn.oid = s.relnamespace
> join pg_depend d on d.refobjid = s.oid and d.refclassid='pg_class'::regclass
> join pg_attrdef ad on ad.oid = d.objid and d.classid = 'pg_attrdef'::regclass
> join pg_attribute col on col.attrelid = ad.adrelid and col.attnum = ad.adnum
> join pg_class tbl on tbl.oid = ad.adrelid
> join pg_namespace n on n.oid = tbl.relnamespace
> where s.relkind = 'S'
> and d.deptype in ('a', 'n')
> and n.nspname = 'public'
> and tbl.relname = 'foo'

Thanks. This assumes that there is only one nextval per table though.
While this holds for the database we need this on right now, it's not a
sufficiently generic solution. How do I, for the sake of paranoia,
specify a column?

Btw, is there a site with recipes showing what's possible to do with the
pg_*-tables?

HM