Re: Toasting more system-table columns

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

From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Mark Hollomon" <mhh@nortelnetworks.com>
Cc: pgsql-hackers@postgreSQL.org
Date: 2000-08-03T19:57:47Z
Lists: pgsql-hackers
"Mark Hollomon" <mhh@nortelnetworks.com> writes:
> Tom Lane wrote:
>> pg_statistic to cope with long
>> min/max/common values (not sure about this).

> I would think pg_statistic would be a 'must'.

Well, it's not a "must" because the code copes fine now (there's a test
in there that simply drops pg_statistic tuples that won't fit).

Question is whether we need good selectivity estimation on columns where
the min/max/common values exceed 8K total (when represented in text form).
Or for that matter whether the estimates we derive from such values are
really useful ...

			regards, tom lane