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From:Johan De Meersman Date:April 29 2010 7:50am
Subject:Re: Slow query on replication master and slave
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I'm sure I answered to this exact post yesterday :-)

On Wed, Apr 28, 2010 at 11:19 PM, Kandy Wong <kandyw@stripped> wrote:

> Hi,
>
> Is it true that the performance of running a query on a live replication
> master and slave has to be much slower than running a query on a static
> server?
>
> I've tried to run the following query on a replication master and it
> takes 1 min 13.76 sec to finish.
> SELECT *, ABS(timeA-1266143632) as distance FROM tableA WHERE timeA -
> 1266143632 <= 0  ORDER BY distance LIMIT 1;
>
> And if I run it on the replication slave, it takes 24.15 sec.
> But if I dump the whole database to another machine as static, it only
> takes 3.70 sec or even less to finish.
>
> The table has 386 columns and timeA is an index.
>
> Is there a way to improve the query or any other factors that would
> affect the performance?
>
> Thanks.
>
> Kandy
>
>
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>


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Is als mosterd by den wyn
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Thread
Slow query on replication master and slaveKandy Wong28 Apr
  • Re: Slow query on replication master and slaveJohan De Meersman29 Apr
    • Re: Slow query on replication master and slaveRick James29 Apr
  • Re: Slow query on replication master and slaveMats Kindahl30 Apr