MySQL--查询表统计信息
=============================================================
show table status like '%waybill5%' \G
## 查看非InnoDB引擎表
SELECT
TABLE_SCHEMA AS database_name,
TABLE_NAME AS table_name,
TABLE_ROWS AS table_rows,
ENGINE AS table_engine,
ROUND((DATA_LENGTH)/1024.0/1024, 2) AS Data_MB,
ROUND((INDEX_LENGTH)/1024.0/1024, 2) AS Index_MB,
ROUND((DATA_LENGTH+INDEX_LENGTH)/1024.0/1024, 2) AS Total_MB,
ROUND((DATA_FREE)/1024.0/1024, 2) AS Free_MB
FROM information_schema.`TABLES` AS T1
WHERE T1.`TABLE_SCHEMA` NOT IN('performance_schema','mysql','information_schema','sys')
AND T1.`ENGINE` NOT IN ('innodb');
==============================================================
查看数据表较大的表
## 查看数据表量较大的表
SELECT
TABLE_SCHEMA AS database_name,
TABLE_NAME AS table_name,
TABLE_ROWS AS table_rows,
ENGINE AS table_engine,
ROUND((DATA_LENGTH)/1024.0/1024, 2) AS Data_MB,
ROUND((INDEX_LENGTH)/1024.0/1024, 2) AS Index_MB,
ROUND((DATA_LENGTH+INDEX_LENGTH)/1024.0/1024, 2) AS Total_MB,
ROUND((DATA_FREE)/1024.0/1024, 2) AS Free_MB
FROM information_schema.`TABLES` AS T1
WHERE T1.`TABLE_SCHEMA` NOT IN('performance_schema','mysql','information_schema')
ORDER BY T1.`TABLE_ROWS` DESC
LIMIT 10; ## 查看数据表空间较大的表
SELECT
TABLE_SCHEMA AS database_name,
TABLE_NAME AS table_name,
TABLE_ROWS AS table_rows,
ENGINE AS table_engine,
ROUND((DATA_LENGTH)/1024.0/1024, 2) AS Data_MB,
ROUND((INDEX_LENGTH)/1024.0/1024, 2) AS Index_MB,
ROUND((DATA_LENGTH+INDEX_LENGTH)/1024.0/1024, 2) AS Total_MB,
ROUND((DATA_FREE)/1024.0/1024, 2) AS Free_MB
FROM information_schema.`TABLES` AS T1
WHERE T1.`TABLE_SCHEMA` NOT IN('performance_schema','mysql','information_schema')
ORDER BY
ROUND((DATA_LENGTH+INDEX_LENGTH)/1024.0/1024, 2)
DESC LIMIT 10;
==============================================================
查看碎片较多的表
## 查看碎片较多的表
SELECT
TABLE_SCHEMA AS database_name,
TABLE_NAME AS table_name,
TABLE_ROWS AS table_rows,
ENGINE AS table_engine,
ROUND((DATA_LENGTH)/1024.0/1024, 2) AS Data_MB,
ROUND((INDEX_LENGTH)/1024.0/1024, 2) AS Index_MB,
ROUND((DATA_LENGTH+INDEX_LENGTH)/1024.0/1024, 2) AS Total_MB,
ROUND((DATA_FREE)/1024.0/1024, 2) AS Free_MB,
ROUND(ROUND((DATA_FREE)/1024.0/1024, 2) /ROUND((DATA_LENGTH+INDEX_LENGTH)/1024.0/1024, 2)*100,2)AS Free_Percent
FROM information_schema.`TABLES` AS T1
WHERE T1.`TABLE_SCHEMA` NOT IN('performance_schema','mysql','information_schema')
AND ROUND(ROUND((DATA_FREE)/1024.0/1024, 2) /ROUND((DATA_LENGTH+INDEX_LENGTH)/1024.0/1024, 2)*100,2) >10
AND ROUND((DATA_FREE)/1024.0/1024, 2)>100
ORDER BY ROUND(ROUND((DATA_FREE)/1024.0/1024, 2) /ROUND((DATA_LENGTH+INDEX_LENGTH)/1024.0/1024, 2)*100,2) DESC
LIMIT 10;
==============================================================
查看表当前自增值
## 查看表自增值
SELECT
T2.TABLE_SCHEMA,
T2.TABLE_NAME,
T1.COLUMN_NAME,
T1.COLUMN_TYPE,
T2.AUTO_INCREMENT
FROM information_schema.columns AS T1
INNER JOIN information_schema.tables AS T2
ON T1.TABLE_SCHEMA=T2.TABLE_SCHEMA
AND T1.TABLE_NAME=T2.TABLE_NAME
WHERE T1.EXTRA='auto_increment'
AND T1.DATA_TYPE NOT LIKE '%bigint%'
ORDER BY T2.AUTO_INCREMENT DESC
LIMIT 100;
==============================================================
查看无主键表
## 查看无主键表
SELECT
TABLE_SCHEMA AS database_name,
TABLE_NAME AS table_name,
TABLE_ROWS AS table_rows,
ENGINE AS table_engine,
ROUND((DATA_LENGTH)/1024.0/1024, 2) AS Data_MB,
ROUND((INDEX_LENGTH)/1024.0/1024, 2) AS Index_MB,
ROUND((DATA_LENGTH+INDEX_LENGTH)/1024.0/1024, 2) AS Total_MB,
ROUND((DATA_FREE)/1024.0/1024, 2) AS Free_MB
FROM information_schema.tables
WHERE (table_schema, table_name) NOT IN (
SELECT DISTINCT table_schema, table_name
FROM information_schema.columns
WHERE COLUMN_KEY = 'PRI'
)
AND table_schema NOT IN ('sys', 'mysql', 'information_schema', 'performance_schema');
MySQL--查询表统计信息的更多相关文章
- Atitit mysql数据库统计信息
Atitit mysql数据库统计信息 SELECT table_name, table_rows, index_length, data_length, auto_increment, create ...
- MySQL的统计信息学习总结
统计信息概念 MySQL统计信息是指数据库通过采样.统计出来的表.索引的相关信息,例如,表的记录数.聚集索引page个数.字段的Cardinality.....MySQL在生成执行计划时,需要根据索引 ...
- mysql收集统计信息
一.手动 执行Analyze table innodb和myisam存储引擎都可以通过执行“Analyze table tablename”来收集表的统计信息,除非执行计划不准确,否则不要轻易执行该 ...
- MySQL索引统计信息更新相关的参数
MySQL统计信息相关的参数: 1. innodb_stats_on_metadata(是否自动更新统计信息),MySQL 5.7中默认为关闭状态 仅在统计信息配置为非持久化的时候生效. 也就是说在i ...
- MySql 查询表结构信息
select Column_name as 列名,is_nullable as 是否可为空,data_type as 数据类型,column_default as 默认值,case when colu ...
- MySQL 8.0 中统计信息直方图的尝试
直方图是表上某个字段在按照一定百分比和规律采样后的数据分布的一种描述,最重要的作用之一就是根据查询条件,预估符合条件的数据量,为sql执行计划的生成提供重要的依据在MySQL 8.0之前的版本中,My ...
- mysql-5.7 持久化统计信息详解
一.持久化统计信息的意义: 统计信息用于指导mysql生成执行计划,执行计划的准确与否直接影响到SQL的执行效率:如果mysql一重启 之前的统计信息就没有了,那么当SQL语句来临时,那么mysql就 ...
- MySQL InnoDB配置统计信息
MySQL InnoDB配置统计信息 1. 配置持久化(Persistent)统计信息参数 1.1 配置自动触发更新统计信息参数 1.2 配置每张表的统计参数 1.3 配置InnoDB优化器统计信息的 ...
- MySQL统计信息以及执行计划预估方式初探
数据库中的统计信息在不同(精确)程度上描述了表中数据的分布情况,执行计划通过统计信息获取符合查询条件的数据大小(行数),来指导执行计划的生成.在以Oracle和SQLServer为代表的商业数据库,和 ...
- sql点滴—mysql中查询表的信息
mysql中查询表的信息 查询mysql表字段信息的sql语句 SHOW DATABASES //列出 MySQL Server 数据库. SHOW TABLES [FROM db_name] //列 ...
随机推荐
- 谈谈http与https
今天简单的来说一下http和https, 简单来讲: HTTP 是 超文本协议,TCP 端口是 80 HTTPS 是一种配合了SSL协议的.加密的HTTP 协议 ,TCP端口是 443 HTTP ...
- splice的多种用法
(一)splice的多种用法: splice(n,m) 从索引n开始删除m个.返回删除项组成新数组 splice(n) 从索引n开始删除到末尾 splice(n,m,x) 从索引n开始删除m个,并且把 ...
- Java基础-面向对象(08)
面向过程 完成一个需求的步骤:首先是搞清楚我们要做什么,然后在分析怎么做,最后我们再代码体现.一步一步去实现,而具体的每一步都需要我们去实现和操作.这些步骤相互调用和协作,完成我们的需求.面向过程开发 ...
- python-day6---流程控制
# if 条件:# 子代码1# 子代码2# 子代码3 # if True:# print('ok')# print('=====?>')# print('=====?>')# print( ...
- Harbor和YUM部署for CentOS 7
Harbor部署for CentOS 7 下载 wget https://storage.googleapis.com/harbor-releases/release-1.7.0/harbor-off ...
- iOS UI-微博案例(通过代码自定义Cell)
一.Model BWWeiBo数据模型 #import <Foundation/Foundation.h> @interface BWWeiBo : NSObject @property ...
- .NET 性能优化方法总结==转
.NET 性能优化方法总结 目录 目录 1. C#语言方面... 4 1.1 垃圾回收... 4 1.1.1 避免不必要的对象创建... 4 1.1.2 不要使用空析构函数 ★... 4 1.1.3 ...
- setuid和setgid
关于有效用户,实际用户的问题,参考: http://www.cnblogs.com/kunhu/p/3699883.html 内核对进程存取文件的许可检查,是通过考查进程的有效用户ID来实现的的. 在 ...
- HttpWebRequest HttpClient
HttpWebRequest HttpClient 简单封装使用,支持https HttpWebRequest using System; using System.Collections.Gener ...
- 关于双网卡双宽带Http及Socks代理的配置
1.[硬件环境] a, 1台宿主(win7)+几十台虚拟机(xp)(vm10的版本,估计可打开52台以上的虚拟机) b, 双网卡,其中一个网卡通过路由连接电信ADSL,一个直连集线器,可直接连接移动m ...