如何查看我的数据库是否有索引?

如果是特定的桌子呢?


当前回答

select
    table_name,
    index_name,
    seq_in_index,
    column_name,
    non_unique,
    index_type,
    comment
from
    information_schema.statistics
where 1=1
    and table_schema = 'my_schema'
    and table_name = 'my_table'
order by 1,2,3,4,5,6

其他回答

如果你想一次性查看所有数据库的所有索引:

use information_schema;
SELECT * FROM statistics;

查询数据库中所有已禁用的索引

SELECT INDEX_SCHEMA, COLUMN_NAME, COMMENT 
FROM information_schema.statistics
WHERE table_schema = 'mydb'
AND COMMENT = 'disabled'

按顺序获取一列中每个索引的所有索引列。

SELECT table_name AS `Table`,
       index_name AS `Index`,
       GROUP_CONCAT(column_name ORDER BY seq_in_index) AS `Columns`
FROM information_schema.statistics
WHERE table_schema = 'sakila'
GROUP BY 1,2;

裁判:http://blog.9minutesnooze.com/mysql-information-schema-indexes/

SHOW INDEX FROM mytable FROM mydb;

SHOW INDEX FROM mydb.mytable;

见文档。

要查看已创建的索引,请使用

SHOW INDEX from your_table_name;

查看表上的所有索引(由DB和您创建)

SHOW EXTENDED INDEX from your_table_name;