Can indexes be deleted in mysql?

Indexes in mysql can be deleted. You can use the "DROP INDEX" statement to delete the index. The syntax format is "DROP INDEX 05b74401f89284067f69c0b2d020259f ON 84b97b20546528f984f83615cb123534" . It is recommended to delete unused indexes because they will slow down the update speed of the table and affect the performance of the database.

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Deleting an index means to delete the table Delete existing indexes. It is recommended to delete unused indexes because they will slow down the update speed of the table and affect the performance of the database. For such an index, it should be deleted.

Basic syntax

When the index is no longer needed, you can use the DROP INDEX statement to delete the index.

Grammar format:

DROP INDEX <索引名> ON <表名>

The syntax description is as follows:

• ec07977447c078c9bd9029f2820ceeb7: The name of the index to be deleted.

• 722e3d59fd24604761db25f00f9b264f: Specify the table name where the index is located.

Example:

Delete the index in the table tb_stu_info. The input SQL statement and execution results are as follows.

mysql> DROP INDEX height
    -> ON tb_stu_info;
Query OK, 0 rows affected (0.27 sec)
Records: 0  Duplicates: 0  Warnings: 0
mysql> SHOW CREATE TABLE tb_stu_info\G
*************************** 1. row ***************************
       Table: tb_stu_info
Create Table: CREATE TABLE `tb_stu_info` (
  `id` int(11) NOT NULL,
  `name` char(45) DEFAULT NULL,
  `dept_id` int(11) DEFAULT NULL,
  `age` int(11) DEFAULT NULL,
  `height` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=gb2312
1 row in set (0.00 sec

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