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Re: Utilize maximum system resources for better performance
Posted by: Rick James
Date: August 09, 2015 11:17PM

> SELECT count(*) as total_results FROM content WHERE content.enabled = 1 ;

takes a long time unless it is in the Query cache. Keep in mind that _any_ change to `total_results` will lose that COUNT from the QC.

How bad is the QC? It depends on far more things that we can discuss here. It _might_ but useful for you. In my experience, 99% of production systems do not benefit from the QC. Yours may be in the 1%.

> mysqli_autocommit($con,FALSE);
> update rows,
> mysqli_commit($con);

That works. Doing the update one row at a time is a lot slower than some form of batching.

I prefer BEGIN; do stuff; COMMIT; instead of using autocommit.

(autocommit is local to your session.)

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Re: Utilize maximum system resources for better performance
August 09, 2015 11:17PM

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