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From:Rob Wultsch Date:April 5 2009 4:12am
Subject:Re: Are equi-joins faster than left joins?
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On Thu, Mar 12, 2009 at 8:41 AM, mos <mos99@stripped> wrote:
> I have 3 tables that are 1:1 and will always have a row for a given
> product,_code & date. If I want to join them together, is it going to be
> faster to use an equi join or a left join, or does it matter?
>

IIRC:With an inner join the optimizer has more latitude to reorganize
the join order and can short circuit the process if there is not a
corresponding row.

This is completely secondary to getting the right result set for your
query. If there is the possibility of a row in the parent table not
joining and needing to be part of the result then you must use left.

-- 
Rob Wultsch
wultsch@stripped
Thread
Are equi-joins faster than left joins?mos3 Apr
  • Re: Are equi-joins faster than left joins?Arthur Fuller4 Apr
  • Re: Are equi-joins faster than left joins?Rob Wultsch5 Apr
  • Re: Are equi-joins faster than left joins?Martijn Tonies5 Apr