Re: pg_migrator to /contrib in a later 9.0 beta

Jesper Krogh wrote:
> On 2010-05-06 06:41, Alvaro Herrera wrote:
> > Excerpts from Jesper Krogh's message of jue may 06 00:32:09 -0400 2010:
> >
> >    
> >> Q: I read you pdf, why isn't statistics copied over? It seems to be the last
> >> part missing from doing an upgrade in a few minutes.
> >>      
> > Seems fraught with peril, and a bit pointless.  What's so bad about having to
> > run ANALYZE afterwards?
> >    
> 
> There is nothing directly "bad" about it.. but:
> 
> It's just "an extra step, that might be overseen and is absolutely 
> required".
> 
> I should have written:
> Why isn't statistics copied over or why doesnt pg_migrator run analyze by
> itself?
> 
> The database (of a reasonable size) is useless until statistics is 
> available.
> 
> I guess it is because pg_dump/restore doesn't do it either.

Yeah, the statistics are part of the system tables, and system tables
are fully handled by pg_dumpall --schema-only (except for statistics). 
There might be changes in the system table statistics format that would
break if pg_migrator tried to migrate the statistics.  Right now
pg_migrator is immune from any system table changes, and I would like to
keep it that way.

And if pg_migrator ran analyze itself, it would greatly increase its
great migration times!

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com