On 2006-02-06, Peter Eisentraut <peter_e(at)gmx(dot)net> wrote:
> I suggest that your problem is the join order (unless you have 500000 
> tables as well).  Moreover, using left joins instead of inner joins 
> seems to be quite useless unless you plan to have tables that are not 
> owned by anyone and are not in a schema.

Perhaps you missed the fact that the query was not one that he wrote,
but is the query that psql uses for \ds ?

>> there is any possibility creating index for pg_authid?
>
> It already has indexes.

True, but they're not being used where you'd expect. This seems to be
something to do with the fact that it's not pg_authid which is being
accessed, but rather the view pg_roles.

-- 
Andrew, Supernews
http://www.supernews.com - individual and corporate NNTP services

In response to

• Re: slow information schema with thausand users, seq.scan pg_authid at 2006-02-06 13:49:13 from Peter Eisentraut

Responses

• Re: slow information schema with thausand users, seq.scan pg_authid at 2006-02-06 17:21:46 from Peter Eisentraut
• Re: slow information schema with thausand users, seq.scan pg_authid at 2006-02-06 19:10:29 from Tom Lane

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