Jim Nasby <jnasby(at)pervasive(dot)com> writes:
> On Jun 18, 2006, at 10:47 PM, Qingqing Zhou wrote:
>> After dump/restore the database size is 1685 MB and after
>> vacuum-full/reindex is 1990 MB. Where we saved 305 MB?
> My guess would be due to toasted text columns...
No, it's probably got more to do with the fact that VACUUM FULL stops
trying to compact a table once it finds a row that it can't move down.
There can be quite a lot of empty space left in the table, if one of the
last rows is significantly wider than the average for the table.
regards, tom lane