我可以运行这个查询来获得MySQL数据库中所有表的大小:
show table status from myDatabaseName;
我希望有人能帮助我理解结果。我在找尺寸最大的桌子。
我应该看哪一列?
当前回答
select x.dbname as db_name, x.table_name as table_name, x.bytesize as the_size from
(select
table_schema as dbname,
sum(index_length+data_length) as bytesize,
table_name
from
information_schema.tables
group by table_schema
) x
where
x.bytesize > 999999
order by x.bytesize desc;
其他回答
你可以使用这个查询来显示表的大小(尽管你需要先替换变量):
SELECT
table_name AS `Table`,
round(((data_length + index_length) / 1024 / 1024), 2) `Size in MB`
FROM information_schema.TABLES
WHERE table_schema = "$DB_NAME"
AND table_name = "$TABLE_NAME";
或者这个查询列出每个数据库中每个表的大小，最大的先:
SELECT
table_schema as `Database`,
table_name AS `Table`,
round(((data_length + index_length) / 1024 / 1024), 2) `Size in MB`
FROM information_schema.TABLES
ORDER BY (data_length + index_length) DESC;
最后计算数据库的总大小:
(SELECT
table_name AS `Table`,
round(((data_length + index_length) / 1024 / 1024), 2) `Size in MB`
FROM information_schema.TABLES
WHERE table_schema = "$DB_NAME"
)
UNION ALL
(SELECT
'TOTAL:',
SUM(round(((data_length + index_length) / 1024 / 1024), 2) )
FROM information_schema.TABLES
WHERE table_schema = "$DB_NAME"
)
select x.dbname as db_name, x.table_name as table_name, x.bytesize as the_size from
(select
table_schema as dbname,
sum(index_length+data_length) as bytesize,
table_name
from
information_schema.tables
group by table_schema
) x
where
x.bytesize > 999999
order by x.bytesize desc;
下面是另一种使用bash命令行的方法。
for i in `mysql -NB -e 'show databases'`; do echo $i; mysql -e "SELECT table_name AS 'Tables', round(((data_length+index_length)/1024/1024),2) 'Size in MB' FROM information_schema.TABLES WHERE table_schema =\"$i\" ORDER BY (data_length + index_length) DESC" ; done
这只是一个供以后参考的说明。所有答案都依赖于I_S.TABLES。例如，如果你在表中有blob字段，它不会告诉你正确的大小。LOB页存储在外部页中，因此不计入聚集索引。 事实上有一个注释:
对于NDB表，该语句的输出显示适当的值 AVG_ROW_LENGTH和DATA_LENGTH列，例外 没有考虑到BLOB列。
我发现InnoDB也是如此。
我已经创建了社区Bug相同。
