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From:Rob Wultsch Date:April 11 2008 3:53pm
Subject:Re: MySQl 5.0 optimization problem
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On Fri, Apr 11, 2008 at 6:47 AM, Ben Clewett <ben@stripped> wrote:
> A COUNT() forces the system to read every row in order to count them...
That is not strictly the case.
A count(field) can use an index scan rather than a sequential scan,
which may or may not be faster. Also some count(field) can queries be
optimized away if a field is NOT NULL and the type is myisam.

Posting a
>Show status;
might be useful.

DDL is always helpful...
-- 
Rob Wultsch
wultsch@stripped
wultsch (aim)
Thread
MySQl 5.0 optimization problemVictor Danilchenko11 Apr
  • Re: MySQl 5.0 optimization problemBen Clewett11 Apr
    • Re: MySQl 5.0 optimization problemWm Mussatto11 Apr
      • Re: MySQl 5.0 optimization problemBen Clewett11 Apr
        • Re: MySQl 5.0 optimization problemVictor Danilchenko11 Apr
    • Re: MySQl 5.0 optimization problemRob Wultsch11 Apr