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Re: bad performances using hashjoin

From: Klint Gore <kg(at)kgb(dot)une(dot)edu(dot)au>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: pgsql-performance(at)postgresql(dot)org,Gaetano Mendola <mendola(at)bigfoot(dot)com>
Subject: Re: bad performances using hashjoin
Date: 2005-02-21 01:30:21
Message-ID: 421939AD2A4.CE73KG@129.180.47.120 (view raw or flat)
Thread:
Lists: pgsql-performance
On Sun, 20 Feb 2005 13:46:10 -0500, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> sat_request rows.  If this is the case you actually need to optimize,
> probably the thing to do is to get rid of the ORDER BY clauses you
> evidently have in your views, so that there's some chance of building
> a fast-start plan.

Is having an order by in a view legal?  In sybase ASA, mssql it throws a
syntax error if there's an order by.

If so, does it do 2 sorts when you sort by something else?

i.e. if view is 
   create view v1 as select * from table order by 1;
and the statment
   select * from v1 order by 2;
is run does it sort by 1 then resort by 2?

klint.

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