Re: pg_upgrade and statistics

Kevin Grittner <kevin.grittner@wicourts.gov>

From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: "Peter Eisentraut" <peter_e@gmx.net>, "Bruce Momjian" <bruce@momjian.us>
Cc: "Daniel Farina" <daniel@heroku.com>,"Greg Stark" <stark@mit.edu>, "pgsql-hackers" <pgsql-hackers@postgresql.org>, "Tom Lane" <tgl@sss.pgh.pa.us>
Date: 2012-03-15T15:20:02Z
Lists: pgsql-hackers
Bruce Momjian <bruce@momjian.us> wrote:
 
> I think we have two choices --- either migrate the statistics, or
> adopt my approach to generating incremental statistics quickly.
> Does anyone see any other options?
 
Would it make any sense to modify the incremental approach to do a
first pass of any tables with target overrides, using the default
GUC setting, and then proceed through the passes you describe for
all tables *except* those?  I'm thinking that any overrides were
probably set because the columns are particularly important in terms
of accurate statistics, and that running with different GUC settings
will just be a waste of time for those tables -- if they have a high
setting for any column, they will sample more blocks for every run,
right?
 
-Kevin