Quickest way to delete enormous MySQL table

mysql innodb
Kyle Kaitan picture Kyle Kaitan · May 18, 2009 · Viewed 48.6k times · Source

I have an enormous MySQL (InnoDB) database with millions of rows in the sessions table that were created by an unrelated, malfunctioning crawler running on the same server as ours. Unfortunately, I have to fix the mess now.

If I try to truncate table sessions; it seems to take an inordinately long time (upwards of 30 minutes). I don't care about the data; I just want to have the table wiped out as quickly as possible. Is there a quicker way, or will I have to just stick it out overnight?

Answer

searlea picture searlea · Jun 14, 2011

(As this turned up high in Google's results, I thought a little more instruction might be handy.)

MySQL has a convenient way to create empty tables like existing tables, and an atomic table rename command. Together, this is a fast way to clear out data:

CREATE TABLE new_foo LIKE foo;

RENAME TABLE foo TO old_foo, new_foo TO foo;

DROP TABLE old_foo;

Done

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