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SHOW INDEXES [FROM|IN] | TiDB SQL Statement Reference
An overview of the usage of SHOW INDEXES [FROM|IN] for the TiDB database.
/docs/dev/sql-statements/sql-statement-show-indexes/
/docs/dev/reference/sql/statements/show-indexes/
/tidb/dev/sql-statement-show-index/
/tidb/dev/sql-statement-show-keys/

SHOW INDEXES [FROM|IN]

The statement SHOW INDEXES [FROM|IN] lists the indexes on a specified table. The statements SHOW INDEX [FROM|IN], SHOW KEYS [FROM|IN] are aliases of this statement, and included for compatibility with MySQL.

Synopsis

ShowIndexStmt ::=
    "SHOW" ( "INDEX" | "INDEXES" | "KEYS" ) ("FROM" | "IN" ) TableName (("FROM" | "IN") SchemaName )? ShowLikeOrWhere?

ShowLikeOrWhere ::=
    "LIKE" SimpleExpr
|   "WHERE" Expression

Examples

mysql> CREATE TABLE t1 (id int not null primary key AUTO_INCREMENT, col1 INT, INDEX(col1));
Query OK, 0 rows affected (0.12 sec)

mysql> SHOW INDEXES FROM t1;
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment | Visible | Expression |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+------------+
| t1    |          0 | PRIMARY  |            1 | id          | A         |           0 |     NULL | NULL   |      | BTREE      |         |               | YES     | NULL       |
| t1    |          1 | col1     |            1 | col1        | A         |           0 |     NULL | NULL   | YES  | BTREE      |         |               | YES     | NULL       |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+------------+
2 rows in set (0.00 sec)

mysql> SHOW INDEX FROM t1;
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment | Visible | Expression |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+------------+
| t1    |          0 | PRIMARY  |            1 | id          | A         |           0 |     NULL | NULL   |      | BTREE      |         |               | YES     | NULL       |
| t1    |          1 | col1     |            1 | col1        | A         |           0 |     NULL | NULL   | YES  | BTREE      |         |               | YES     | NULL       |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+------------+
2 rows in set (0.00 sec)

mysql> SHOW KEYS FROM t1;
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+------------+
| Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment | Visible | Expression |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+------------+
| t1    |          0 | PRIMARY  |            1 | id          | A         |           0 |     NULL | NULL   |      | BTREE      |         |               | YES     | NULL       |
| t1    |          1 | col1     |            1 | col1        | A         |           0 |     NULL | NULL   | YES  | BTREE      |         |               | YES     | NULL       |
+-------+------------+----------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+---------+------------+
2 rows in set (0.00 sec)

Note that TiDB accepts index types such as HASH, BTREE and RTREE in syntax for compatibility with MySQL, but ignores them.

MySQL compatibility

The SHOW INDEXES [FROM|IN] statement in TiDB is fully compatible with MySQL. If you find any compatibility differences, report a bug.

See also