MySQL

备份整个数据库

mysqldump -u root -p --all-databases > mysql.sql

查询数据表占用空间

SELECT table_schema AS `Database`,
       table_name AS `Table`,
       round(((data_length + index_length) / 1024 / 1024), 2) `Size in MB`
FROM information_schema.TABLES
ORDER BY (data_length + index_length) DESC;

优化表空间

OPTIMIZE table ANY_TABLE_NAME;