Re: Recreate primary key without dropping foreign keys?

Am 16.04.2012 10:32, schrieb Chris Ernst:
> On 04/15/2012 10:57 PM, Frank Lanitz wrote:
>> On Sun, 15 Apr 2012 18:41:05 -0600 Chris Ernst <cernst@zvelo.com>
>> wrote:
>>
>>> Hi all,
>>>
>>> In PostgreSQL 9.1.3, I have a few fairly large tables with
>>> bloated primary key indexes.  I'm trying to replace them using
>>> newly created unique indexes as outlined in the docs.  Something
>>> like:
>>>
>>> CREATE UNIQUE INDEX CONCURRENTLY dist_id_temp_idx ON
>>> distributors (dist_id); ALTER TABLE distributors DROP CONSTRAINT
>>> distributors_pkey, ADD CONSTRAINT distributors_pkey PRIMARY KEY
>>> USING INDEX dist_id_temp_idx;
>>>
>>> However, the initial drop of the primary key constraint fails
>>> because there are a whole bunch of foreign keys depending on it.
>>>
>>> I've done some searching and haven't found a workable solution.
>>> Is there any way to swap in the new index for the primary key
>>> constraint without dropping all dependent foreign keys?  Or am I
>>> pretty much stuck with dropping and recreating all of the foreign
>>> keys?
>>
>> REINDEX is not working here?
>
> Hi Frank,
>
> Thanks, but REINDEX is not an option as it would take an exclusive
> lock on the table for several hours.

Well, from my little view I guess all rebuilding index action would
require such, as its the primary key with uniqueness. I'd think of a
complete reinit of the cluster with pg_dump and restoring, but this
would also need a downtime at least for write access.

Why is the index so bloated?

Cheers,
Frank