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This article is about how mysql removes fields. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

In mysql, you can use the "ALTER TABLE" statement and the "DROP" keyword to remove the specified field. The syntax is "ALTER TABLE data table name DROP field name;", "field name" refers to the name of the field that needs to be removed from the table.

The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.

In mysql, you can use the "ALTER TABLE" statement and the "DROP" keyword to remove the specified field.

ALTER TABLE statement to change the structure of the original table, such as adding or deleting columns, changing the original column type, renaming columns or tables, and so on.

The drop statement removes the structure of the table, as well as dependent constraints (constrain), triggers (trigger), and indexes (index).

To remove a field is to remove a field from the data table. The syntax format is as follows:

ALTER TABLE Datasheet name DROP field name

Where Field name refers to the name of the field that needs to be deleted from the table.

Example: remove the deptId field from the tb_emp data table

First look at the data of the tb_emp data table

Mysql > DESC tb_emp +-+-+ | Field | Type | Null | Key | Default | Extra | + -+ | id | int (11) | YES | | NULL | name | varchar (30) | YES | | NULL | | deptId | int (11) | YES | | NULL | | salary | float | YES | | NULL | | + -+ 5 rows in set (0.01 sec)

Remove deptId field

Mysql > ALTER TABLE tb_emp-> DROP deptId;Query OK, 0 rows affected (.53 sec) Records: 0 Duplicates: 0 Warnings: 0

View the new data after removing the field

Mysql > DESC tb_emp +-+-+ | Field | Type | Null | Key | Default | Extra | + -+ | id | int (11) | YES | | NULL | | name | varchar (30) | YES | | NULL | | salary | float | YES | | NULL | | +-+-+ 5 Rows in set (0.00 sec) Thank you for your reading! This is the end of this article on "how to remove fields from mysql". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, you can share it out for more people to see!

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