MySQL

目录

• mysql 使用insert-select快速造出大量测试数据
• 查看mysql数据库容量

1 mysql 使用insert-select快速造出大量测试数据

insert-select的原理是将表中数据查出后，再次插入数据库，这样数据就会成倍增长。

• use 库建表

CREATE TABLE `review` (
`review_id` INT(11) NOT NULL AUTO_INCREMENT,
`movie_id` INT(11) NOT NULL,
`content` VARCHAR(1024) NOT NULL,
PRIMARY KEY (`review_id`)
)
COLLATE='utf8_general_ci'
ENGINE=InnoDB;

• 首先使用如下语句插入10条数据，主键任其自增

insert into review(movie_id,content) values(1,now());

• 然后使用insert-select方法成倍插入数据

insert into review(movie_id,content) select movie_id,content from review;

• 查看review表数据行数

select count(*) from review;

2 查看mysql数据库容量

• 查询所有数据库的总大小

use information_schema;
select concat(round(sum(DATA_LENGTH/1024/1024),2),'MB') as data from TABLES;

• 统计一下所有库数据量

# 每张表数据量=AVG_ROW_LENGTH*TABLE_ROWS+INDEX_LENGTH
SELECT
SUM(AVG_ROW_LENGTH*TABLE_ROWS+INDEX_LENGTH)/1024/1024 AS total_mb
FROM information_schema.TABLES;

• 统计每个库大小：

SELECT
table_schema,SUM(AVG_ROW_LENGTH*TABLE_ROWS+INDEX_LENGTH)/1024/1024 AS total_mb
FROM information_schema.TABLES group by table_schema;

• 查看指定数据库的大小，比如说：数据库test

use information_schema;
select concat(round(sum(DATA_LENGTH/1024/1024),2),'MB') as data from TABLES where table_schema='test';

• 查看所有数据库各容量大小

select
table_schema as '数据库',
sum(table_rows) as '记录数',
sum(truncate(data_length/1024/1024, 2)) as '数据容量(MB)',
sum(truncate(index_length/1024/1024, 2)) as '索引容量(MB)'
from information_schema.tables
group by table_schema
order by sum(data_length) desc, sum(index_length) desc;

• 查看所有数据库各表容量大小

select
table_schema as '数据库',
table_name as '表名',
table_rows as '记录数',
truncate(data_length/1024/1024, 2) as '数据容量(MB)',
truncate(index_length/1024/1024, 2) as '索引容量(MB)'
from information_schema.tables
order by data_length desc, index_length desc;

• 查看指定数据库容量大小

# 例：查看mysql库容量大小
select
table_schema as '数据库',
sum(table_rows) as '记录数',
sum(truncate(data_length/1024/1024, 2)) as '数据容量(MB)',
sum(truncate(index_length/1024/1024, 2)) as '索引容量(MB)'
from information_schema.tables
where table_schema='mysql';　

• 查看指定数据库各表容量大小

例：查看mysql库各表容量大小
select
table_schema as '数据库',
table_name as '表名',
table_rows as '记录数',
truncate(data_length/1024/1024, 2) as '数据容量(MB)',
truncate(index_length/1024/1024, 2) as '索引容量(MB)'
from information_schema.tables
where table_schema='mysql'
order by data_length desc, index_length desc;

参考文档：

• 转自： https://www.yuque.com/u1300481/kb/vpodkg
• 转自： https://www.cnblogs.com/--smile/p/11451238.html