MySQL queries - how expensive are they really?

Posted by incrediman on Stack Overflow See other posts from Stack Overflow or by incrediman
Published on 2010-03-18T11:57:56Z Indexed on 2010/03/18 12:01 UTC
Read the original article Hit count: 546

Filed under:

php

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mysql

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mysql-query

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cost

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optimization

I've heard that mysql queries are very expensive, and that you should avoid at all costs making too many of them.

I'm developing a site that will be used by quite a few people, and I'm wondering:

How expensive are mysql queries actually? If I have 400,000 people in my database, how expensive is it to query it for one of them?

How close attention do I need to pay that I don't make too many queries per client request?

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