MySQL如何查看某个表所占空间大小

SELECT 
    table_schema AS '数据库名',
    table_name AS '表名',
    ROUND(data_length/1024/1024, 2) AS '数据大小(MB)',
    ROUND(index_length/1024/1024, 2) AS '索引大小(MB)',
    ROUND((data_length + index_length)/1024/1024, 2) AS '总大小(MB)',
    table_rows AS '行数'
FROM 
    information_schema.TABLES 
WHERE 
    table_schema NOT IN ('information_schema', 'mysql', 'performance_schema')
ORDER BY 
    (data_length + index_length) DESC;

SELECT round(data_length/1024/1024, 2) AS '数据大小(MB)', round(index_length/1024/1024, 2) AS '索引大小(MB)', round((data_length + index_length)/1024/1024, 2) AS '总大小(MB)'
FROM information_schema.TABLES 
where table_name = '表名';

SELECT 
    table_name AS '表名',
    ROUND(data_length/1024/1024, 2) AS '数据大小(MB)',
    ROUND(index_length/1024/1024, 2) AS '索引大小(MB)',
    ROUND((data_length + index_length)/1024/1024, 2) AS '总大小(MB)',
    table_rows AS '行数'
FROM 
    information_schema.TABLES 
WHERE 
    table_schema = '你的数据库名'
ORDER BY 
    (data_length + index_length) DESC;

SELECT 
    table_name AS '表名',
    engine AS '存储引擎',
    ROUND(data_length/1024/1024, 2) AS '数据大小(MB)',
    ROUND(index_length/1024/1024, 2) AS '索引大小(MB)',
    ROUND((data_length + index_length)/1024/1024, 2) AS '总大小(MB)',
    ROUND(data_free/1024/1024, 2) AS '碎片空间(MB)',
    table_rows AS '行数',
    avg_row_length AS '平均行长度(字节)',
    create_time AS '创建时间',
    update_time AS '更新时间'
FROM 
    information_schema.TABLES 
WHERE 
    table_schema = '你的数据库名'
    AND table_name = '你的表名';

mysql -u用户名 -p密码 -e "SELECT table_name AS '表名', \
ROUND(data_length/1024/1024,2) AS '数据大小(MB)', \
ROUND(index_length/1024/1024,2) AS '索引大小(MB)', \
ROUND((data_length+index_length)/1024/1024,2) AS '总大小(MB)' \
FROM information_schema.TABLES \
WHERE table_schema='你的数据库名' \
ORDER BY (data_length+index_length) DESC;"

# 切换到MySQL数据目录
cd /var/lib/mysql/你的数据库名/

# 查看文件大小
ls -lh *.ibd *.frm *.MYD *.MYI

# 计算总大小
du -sh ./*

SHOW TABLE STATUS FROM 你的数据库名 LIKE '你的表名'\G

SHOW ENGINE INNODB STATUS\G

SELECT 
    FILE_NAME, 
    TABLESPACE_NAME, 
    ENGINE, 
    TOTAL_EXTENTS, 
    EXTENT_SIZE, 
    INITIAL_SIZE, 
    MAXIMUM_SIZE 
FROM 
    INFORMATION_SCHEMA.FILES 
WHERE 
    FILE_TYPE = 'DATAFILE';

pt-diskstats --devices=/var/lib/mysql

pt-mysql-summary --user=用户名 --password=密码

mysqldumpslow -s t /var/log/mysql/mysql-slow.log

SELECT 
    table_schema AS '数据库',
    table_name AS '表名',
    ROUND(data_free/1024/1024, 2) AS '碎片空间(MB)',
    ROUND((data_length + index_length)/1024/1024, 2) AS '总大小(MB)',
    ROUND((data_free/(data_length + index_length + data_free))*100, 2) AS '碎片率(%)'
FROM 
    information_schema.TABLES 
WHERE 
    table_schema NOT IN ('information_schema', 'mysql', 'performance_schema')
    AND data_free > 0
ORDER BY 
    data_free DESC
LIMIT 10;

SELECT 
    table_name, 
    engine, 
    row_format, 
    create_options 
FROM 
    information_schema.TABLES 
WHERE 
    table_schema = '你的数据库名';

#!/bin/bash

# MySQL表空间监控脚本
DB_USER="用户名"
DB_PASS="密码"
DB_NAME="数据库名"
OUTPUT_FILE="/tmp/mysql_table_sizes_$(date +%Y%m%d).csv"

echo "表名,数据大小(MB),索引大小(MB),总大小(MB),行数,碎片空间(MB)" > $OUTPUT_FILE

mysql -u$DB_USER -p$DB_PASS -e "SELECT \
    CONCAT(table_name, ',', \
    ROUND(data_length/1024/1024, 2), ',', \
    ROUND(index_length/1024/1024, 2), ',', \
    ROUND((data_length + index_length)/1024/1024, 2), ',', \
    table_rows, ',', \
    ROUND(data_free/1024/1024, 2)) \
FROM information_schema.TABLES \
WHERE table_schema = '$DB_NAME' \
ORDER BY (data_length + index_length) DESC;" >> $OUTPUT_FILE

​​​​​​​echo "报告已生成: $OUTPUT_FILE"