MySQL表空间碎片怎么查？一文教你清理磁盘碎片

SELECT 
    table_schema AS `Database`, 
    table_name AS `Table`, 
    ROUND(data_length / 1024 / 1024, 2) AS `Data Size (MB)`, 
    ROUND(index_length / 1024 / 1024, 2) AS `Index Size (MB)`, 
    ROUND(data_free / 1024 / 1024, 2) AS `Free Space (MB)`
FROM 
    information_schema.tables
WHERE 
    table_schema NOT IN ('information_schema', 'performance_schema', 'mysql', 'sys')
ORDER BY 
    data_length + index_length DESC;

OPTIMIZE TABLE your_table_name;

SET @tables = NULL;
SELECT GROUP_CONCAT(table_name) INTO @tables
FROM information_schema.tables 
WHERE table_schema = 'your_database_name' AND table_type = 'BASE TABLE';

SET @tables = CONCAT('OPTIMIZE TABLE ', @tables);
PREPARE stmt FROM @tables;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

SHOW TABLE STATUS LIKE 'your_table_name';

[mysqld]
innodb_file_per_table=1

#!/bin/bash

# MySQL 登录信息
MYSQL_USER="mysql_user"
MYSQL_PASSWORD="mysql_password"
MYSQL_HOST="localhost"
MYSQL_DATABASE="database_name"

# 获取所有表名
TABLES=$(mysql -u$MYSQL_USER -p$MYSQL_PASSWORD -h$MYSQL_HOST -D$MYSQL_DATABASE -e "SHOW TABLES;" | awk '{ print $1}' | grep -v '^Tables')

# 对每个表执行 OPTIMIZE TABLE
for TABLE in $TABLES; do
    echo "Optimizing table: $TABLE"
    mysql -u$MYSQL_USER -p$MYSQL_PASSWORD -h$MYSQL_HOST -D$MYSQL_DATABASE -e "OPTIMIZE TABLE $TABLE;"
done

echo "Table optimization complete."

exit 0