Re: pg_upgrade and statistics

On tis, 2012-03-13 at 20:34 -0400, Bruce Momjian wrote:
> I frankly am worried that if we copy over statistics even in ASCII
> that don't match what the server expects, it might lead to a crash,
> which has me back to wanting to speed up vacuumdb.

Why can't we maintain a conversion routine for statistics from older
versions?  It's not like the statistics layout changes every week.
pg_dump could print out something like

SELECT pg_restore_statistics(catversion, tablename, ... some data ...);
...

and that function would have the knowledge to convert the data and
insert it back into pg_statistic and pg_class.

That can't be that hard considering all the other work we put into
backward compatibility and upgrade capability.