MySQL查看数据库表容量大小 Mysql查看表的字段数量

1.查看所有数据库容量大小

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 
group by table_schema 
order by sum(data_length) desc, sum(index_length) desc;

2.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 
where table_schema='请修改要查看的数据库名称'
order by data_length desc, index_length desc;

3.查看所有数据库各表容量大小及各表的字段数量

select tb.table_schema as '数据库',
tb.table_name as '表名',
tb.table_rows as '记录数'
,truncate(tb.data_length/1024/1024, 2) as '数据容量(MB)'
,truncate(tb.index_length/1024/1024, 2) as '索引容量(MB)'
,(select count(*) from information_schema.COLUMNS where TABLE_SCHEMA=tb.table_schema and table_name=tb.table_name) as '字段数量'
from information_schema.tables as tb
where tb.table_schema='请修改成你要查看的数据库名'
order by tb.table_name,tb.data_length desc, tb.index_length desc;