The following bug has been logged online:

Bug reference: 2733
Logged by: Basil Evseenko
Email address: evseenko (AT) sysoft (DOT) ru
PostgreSQL version: 8.2beta2
Operating system: Linux 2.6
Description: pg_get_serial_sequence error (addition: may be tsearch2
related)
Details:

On 8.1.5:
select pg_catalog.pg_get_serial_sequence('album', 'id');
pg_get_serial_sequence
------------------------------
tables.album_id_seq

On 8.2beta2 (with contrib/tsearch2)

select pg_catalog.pg_get_serial_sequence('album', 'id');
pg_get_serial_sequence
----------------------------------------
tables.album_title_lower2_idx

So pg_catalog.pg_get_serial_sequence return garbage: index name vs sequence
name

This bug seems only affected tables, that have
tsearch2 columns/indexes installed.

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