MySQL has an OPTIMIZE TABLE command which can be used to reclaim unused space in a MySQL install. Is there a way (built-in command or common stored procedure) to run this o
You can use mysqlcheck to do this at the command line.
One database:
mysqlcheck -o <db_schema_name>
All databases:
mysqlcheck -o --all-databases
I made this 'simple' script:
set @tables_like = null;
set @optimize = null;
set @show_tables = concat("show tables where", ifnull(concat(" `Tables_in_", database(), "` like '", @tables_like, "' and"), ''), " (@optimize:=concat_ws(',',@optimize,`Tables_in_", database() ,"`))");
Prepare `bd` from @show_tables;
EXECUTE `bd`;
DEALLOCATE PREPARE `bd`;
set @optimize := concat('optimize table ', @optimize);
PREPARE `sql` FROM @optimize;
EXECUTE `sql`;
DEALLOCATE PREPARE `sql`;
set @show_tables = null, @optimize = null, @tables_like = null;
To run it, simply paste it in any SQL IDE connected to your database.
Notice: this code WON'T work on phpmyadmin.
It runs a show tables
statement and stores it in a prepared statement. Then it runs a optimize table
in the selected set.
You can control which tables to optimize by setting a different value in the var @tables_like
(e.g.: set @tables_like = '%test%';
).
You can optimize/check and repair all the tables of database, using mysql client.
First, you should get all the tables list, separated with ',':
mysql -u[USERNAME] -p[PASSWORD] -Bse 'show tables' [DB_NAME]|xargs|perl -pe 's/ /,/g'
Now, when you have all the tables list for optimization:
mysql -u[USERNAME] -p[PASSWORD] -Bse 'optimize tables [tables list]' [DB_NAME]
my 2cents: start with table with highest fragmentation
for table in `mysql -sss -e "select concat(table_schema,".",table_name) from information_schema.tables where table_schema not in ('mysql','information_schema','performance_schema') order by data_free desc;"
do
mysql -e "OPTIMIZE TABLE $table;"
done
From phpMyAdmin and other sources you can use:
SET SESSION group_concat_max_len = 99999999;
SELECT GROUP_CONCAT(concat('OPTIMIZE TABLE `', table_name, '`;') SEPARATOR '') AS O
FROM INFORMATION_SCHEMA.TABLES WHERE
TABLE_TYPE = 'BASE TABLE'
AND table_name!='dual'
AND TABLE_SCHEMA = '<your databasename>'
Then you can copy & paste the result to a new query or execute it from your own source. If you don't see the whole statement:
The MySQL Administrator
(part of the MySQL GUI Tools) can do that for you on a database level.
Just select your schema and press the Maintenance
button in the bottom right corner.
Since the GUI Tools have reached End-of-life status they are hard to find on the mysql page. Found them via Google: http://dev.mysql.com/downloads/gui-tools/5.0.html
I don't know if the new MySQL Workbench can do that, too.
And you can use the mysqlcheck
command line tool which should be able to do that, too.