[postgis-users] (no subject)

[Mark Cave-Ayland]

On 12/04/11 17:38, Paul & Caroline Lewis wrote:

> Hi,
> Thank you Mark and Richard for your replies. Having looked at this it
> seems a Full Vacuum is the answer, however I'm not sure why. Processing
> the SQL scripts as originall reported I do get a large table from
> TestSet1 and a small table from TestSet2. Once a Full vacuum is
> performed on the large table from TestSet1 its size drops to the same as
> the small table from TestS2, however adding a full vacuum into the
> TestSet1 procedure makes it slower to run than TestSet2, very much
> slower especially on uploading the very large data sets (70 mill rows).
> This begs the question is TestSet2 very efficient or is it missing
> something fundamental that a Full Vacuum provides that I'm not realising
> at the moment.

That's strange - do you see the same behaviour if you swap the order of 
the data load, i.e. do the ordered data set first, and/or use a 
different table name for each load? I'm just wondering if you're seeing 
some kind of database bloat if VACUUM fixes the issue.


ATB,

Mark.

-- 
Mark Cave-Ayland - Senior Technical Architect
PostgreSQL - PostGIS
Sirius Corporation plc - control through freedom
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