如何查看在MySQL中设置的索引？
要查看索引，可以使用SHOW命令。
以下是语法-
show index from yourTableName;
让我们首先创建一个表-
mysql> create table DemoTable ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, FirstName varchar(20), LastName varchar(20) );
以下是创建索引的查询-
mysql> create index id_FirstName on DemoTable(Id,FirstName); Records : 0 Duplicates : 0 Warnings : 0
以下是查询以查看我在MySQL中设置的索引的查询-
mysql> show index from DemoTable;
这将产生以下显示索引的输出-
+--------------+------------+--------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+ | Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment | Visible | +--------------+------------+--------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+ | DemoTable | 0 | PRIMARY | 1 | Id | A | 0 | NULL | NULL | | BTREE | | | YES | | DemoTable | 1 | id_FirstName | 1 | Id | A | 0 | NULL | NULL | | BTREE | | | YES | | DemoTable | 1 | id_FirstName | 2 | FirstName | A | 0 | NULL | NULL | YES | BTREE | | | YES | +--------------+------------+--------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+ 3 rows in set (0.26 sec)