the Memory problem about MySQL "SELECT *"

Posted by Austin Huang on Stack Overflow See other posts from Stack Overflow or by Austin Huang
Published on 2010-12-30T01:47:19Z Indexed on 2010/12/30 1:53 UTC
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python

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mysql

Dear all:

I'm new to MySQL, and I have a question about the memory.

I have a 200mb table(MyISAM, 2,000,000 rows), and I try to load all of it to the memory.

I use python(actually MySQLdb in python) with sql: SELECT * FROM table.

However, from my linux "top" I saw this python process uses 50% of my memory(which is total 6GB)

I'm curious about why it uses about 3GB memory only for a 200 mb table. Thanks in advance!

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