MySQL information_schema doesn't update I have a database, say abc, in mysql server. It has only one table named test. test uses innodb engine and I've set innodb_file_per_table to true.

After I run the query delete from abc.test, I want to calculate the database size of abc. Here is the query I use:

SELECT
    table_schema "name",
    sum( IF(engine = "MyISAM", data_length + index_length -  data_free,
    data_length + index_length)) "size"
FROM information_schema.TABLES
where table_schema like "abc";


The strange thing is that I find the database size doesn't decrease at all, however the data in "test" is gone.

I've done this kind of test many times, this strange behavior happens sometimes.

I'm using percona mysql server 5.5.29-rel29.4.

Can anybody tell me what is wrong? 

Update:

Actually, I use another thread to check the database size periodically.
You need to rebuild the table in order to shrink the ibd file. This command will do it:

optimize table abc.test;