# **DROP INDEX**

## **Grammar Description**

This statement is used to delete the index from the currently selected table, and an error will be reported if the index does not exist unless the `IF EXISTS` modifier is used.

## **Grammar Structure**

```sql
DROP INDEX index_name ON tbl_name
```

## **Example**

```text
create table t5(a int, b int, unique key(a));
mysql> show create table t5;
+------------------------------------------------------------------------------------------------------------------------------
| Table | Create Table |
+------------------------------------------------------------------------------------------------------------------------------
| t5 | CREATE TABLE `t5` (
`a` INT DEFAULT NULL,
`b` INT DEFAULT NULL,
UNIQUE KEY `a` (`a`)
) |
+------------------------------------------------------------------------------------------------------------------------------
1 row in set (0.01 sec)

create index b on t5(b);
mysql> show create table t5;
+------------------------------------------------------------------------------------------------------------------------------
| Table | Create Table |
+------------------------------------------------------------------------------------------------------------------------------
| t5 | CREATE TABLE `t5` (
`a` INT DEFAULT NULL,
`b` INT DEFAULT NULL,
UNIQUE KEY `a` (`a`),
KEY `b` (`b`)
) |
+------------------------------------------------------------------------------------------------------------------------------
1 row in set (0.02 sec)

drop index b on t5;
mysql> show create table t5;
+------------------------------------------------------------------------------------------------------------------------------
| Table | Create Table |
+------------------------------------------------------------------------------------------------------------------------------
| t5 | CREATE TABLE `t5` (
`a` INT DEFAULT NULL,
`b` INT DEFAULT NULL,
UNIQUE KEY `a` (`a`)
) |
+------------------------------------------------------------------------------------------------------------------------------
1 row in set (0.02 sec)
```