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From:Jeff Smelser Date:December 23 2004 8:24pm
Subject:Re: scanning 2 rows slow index fast 26GB MyISAM
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On Thursday 23 December 2004 02:01 pm, Bryan Heitman wrote:
> Hi Sergio,
>
> All of your suggestions deal with key optimization, I do not believe I have
> a key issue here.  Remember that select count(*), an index-only query
> returns in .06 seconds which is very quick.  The real question, is why does
> it take 5 mins to retrieve the row data for these 2 rows that the index
> retrieved so quickly.  Why the delay and why the heavy read activity on the
> MYD file.

Do a show table status. It shows the number of rows in a table. It knows this 
well before you run select count(*), so it really doesnt count anything. 

So the select count(*) theory isnt correct.

Jeff

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scanning 2 rows slow index fast 26GB MyISAMBryan Heitman23 Dec
  • Re: scanning 2 rows slow index fast 26GB MyISAMSergio Salvi23 Dec
    • Re: scanning 2 rows slow index fast 26GB MyISAMBryan Heitman23 Dec
      • Re: scanning 2 rows slow index fast 26GB MyISAMSergio Salvi23 Dec
        • Re: scanning 2 rows slow index fast 26GB MyISAMBryan Heitman23 Dec
          • Re: scanning 2 rows slow index fast 26GB MyISAMJeff Smelser23 Dec
          • RE: scanning 2 rows slow index fast 26GB MyISAMDonny Simonton23 Dec
            • Re: scanning 2 rows slow index fast 26GB MyISAMBryan Heitman23 Dec
  • Re: scanning 2 rows slow index fast 26GB MyISAMBenoit St-Jean23 Dec
Re: scanning 2 rows slow index fast 26GB MyISAMBryan Heitman23 Dec