Re: 15,000 tables - Mailing list pgsql-performance

From Alex Stapleton
Subject Re: 15,000 tables
Date
Msg-id 57292C7A-8300-4CD4-BF1E-62190D36A549@advfn.com
Whole thread Raw
In response to Re: 15,000 tables  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: 15,000 tables  (Alex Stapleton <alexs@advfn.com>)
List pgsql-performance
On 1 Dec 2005, at 16:03, Tom Lane wrote:

> Michael Riess <mlriess@gmx.de> writes:
>> (We NEED that many tables, please don't recommend to reduce them)
>
> No, you don't.  Add an additional key column to fold together
> different
> tables of the same structure.  This will be much more efficient than
> managing that key at the filesystem level, which is what you're
> effectively doing now.
>
> (If you really have 15000 distinct rowtypes, I'd like to know what
> your database design is...)
>

Won't you end up with awful seek times if you just want data which
previously been stored in a single table? E.g. whilst before you
wanted 1000 contiguous rows from the table, now you want 1000 rows
which now have 1000 rows you don't care about in between each one you
do want.

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