Re: big database with very small dump !?

On Mon, 2008-08-11 at 12:45 -0400, Greg Smith wrote:
> On Mon, 11 Aug 2008, Joao Ferreira gmail wrote:
>
> > I'm finding it very strange that my pg takes 9Giga on disk but
> > pg_dumpall produces a 250Mega dump. 'VACUUM FULL' was executed
> > yesterday.
>
> If you've been running VACUUM FULL, it's probably so-called "index bloat".
> Try running the query at http://wiki.postgresql.org/wiki/Disk_Usage to
> figure out where all your space has gone inside the database.
>

egbert=# SELECT nspname || '.' || relname AS "relation",
egbert-# pg_size_pretty(pg_relation_size(nspname || '.' || relname))
AS "size"
egbert-# FROM pg_class C
egbert-# LEFT JOIN pg_namespace N ON (N.oid = C.relnamespace)
egbert-# WHERE nspname NOT IN ('pg_catalog', 'information_schema')
egbert-# AND nspname !~ '^pg_toast'
egbert-# AND pg_relation_size(nspname || '.' || relname)>0
egbert-# ORDER BY pg_relation_size(nspname || '.' || relname) DESC
egbert-# LIMIT 20;

relation | size
----------------------------------+---------
public.timeslots_strs_var_ts_key | 5643 MB #this is a UNIQUE clause
public.timeslots | 2660 MB #this is the only table
public.timeslots_timestamp_index | 583 MB #this is an index
public.timeslots_var_index | 314 MB #this is an index
public.timeslots_timeslot_index | 275 MB "this is an index
(5 rows)

so it seems that the UNIQUE clause is taking up more space than the data
itself...

stil I have 2660 MB of data but the dump is about 10x smaller !!!

any hints ?

> --
> * Greg Smith gsmith(at)gregsmith(dot)com http://www.gregsmith.com Baltimore, MD
>