After writing SQL statements in MySQL, how to measure the speed / performance of them?

Posted by Jian Lin on Stack Overflow See other posts from Stack Overflow or by Jian Lin
Published on 2010-04-24T16:00:31Z Indexed on 2010/04/24 16:03 UTC
Read the original article Hit count: 444

Filed under:

mysql

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sql

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performance-comparison

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query-execution-plans

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performance-tuning

I saw something from an "execution plan" article:

10 rows fetched in 0.0003s (0.7344s)

How come there are 2 durations shown? What if I don't have large data set yet. For example, if I have only 20, 50, or even just 100 records, I can't really measure how faster 2 different SQL statements compare in term of speed in real life situation? In other words, there needs to be at least hundreds of thousands of records, or even a million records to accurately compares the performance of 2 different SQL statements?

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