What does /*!40001 SQL_NO_CACHE */ * means

[mister_v]

Hi,

From time to time i check my mysql-slow log:
/var/log/mysql/mysql-slow.log

Last time I saw a query with this:

Code: Select all

SELECT /*!40001 SQL_NO_CACHE */ * FROM db

But I don't have script that runs with this in the query.
where does it come from?
Is some one else accessing my MySQL-server?

[chris]

This query is almost certainly due to a mysql dump being run on the database.
Those are the style of queries it submits to extract the data for the dump.

Check for the time when it happens, it might be a backup that is running.

Code: Select all

# Time: 130219 18:11:35
# User@Host: user[host] @ localhost []
# Query_time: 1.807723  Lock_time: 0.000104 Rows_sent: 0  Rows_examined: 4706
SET timestamp=1361293895;
SELECT /*!40001 SQL_NO_CACHE */ * FROM db;

This line Time: 130219 18:11:35
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