Re: Stats for inheritance trees

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: decibel <decibel@decibel.org>
Cc: pgsql-hackers@postgresql.org
Date: 2010-01-06T15:03:28Z
Lists: pgsql-hackers
decibel <decibel@decibel.org> writes:
> On Dec 29, 2009, at 6:29 PM, Tom Lane wrote:
>> * when a tabstat message comes in, increment changes_since_analyze by
>> the sum of t_tuples_inserted + t_tuples_updated + t_tuples_deleted;
>> 
>> * when an analyze report message comes in, reset changes_since_analyze
>> to zero.

> If that's being added, could we extend the concept to also keep a reltuples_delta column (name suggestions welcome!) that is = reltuples_delta + t_tuples_inserted - t_tuples_deleted, and then set reltuples_delta back to 0 after an analyze (or anything else that would reset reltuples)? That means you could use reltuples + reltuples_delta as a fairly accurate row count.

We already have a fairly accurate row count.

			regards, tom lane