Re: pg_dump and diffrent sizes

On Fri, 2006-03-03 at 14:10, Maciej Piekielniak wrote:
> Hello pgsql-sql,
> 
> I dump db with pg_dump v.8.1.3 on database postgresql server 7.4.7.
> Data directory with my db on pg 7.4.7 had 1,8GB and
> file with dump had 2,7GB.
> Database have blob fields.
> 
> When I restore db on pg 8.1 - data directory have only 1GB, why?

I would guess that you have lots of highly compressible text entries,
and postgresql is compressing them for you.  The difference in size
between 7.4 and 8.1 is likely due to unrecycled tuples in the data
store.  Even with regular vacuuming, some small percentage of dead
tuples is normal.