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How to add comments to table in mysql

王林

Sep 02, 2020 pm 03:29 PM

mysqlCommentsurface

Mysql method to add comments to the table: You can use the comment keyword to add, the specific method is [create table user(in int, name varchar(30))comment = 'User information table';].

How to add comments to table in mysql

#In MySQL, add comments to tables and fields using the COMMENT keyword.

Related learning recommendations: mysql tutorial (video)

1. Add comments on tables and fields

Create a data table At the same time, add comments to tables and fields.

CREATE TABLE tb_user
(
	id INT AUTO_INCREMENT PRIMARY KEY COMMENT &#39;编号&#39;,
	name VARCHAR(30) COMMENT &#39;姓名&#39;
)COMMENT = &#39;用户信息表&#39;;

2. Modify table comments

ALTER TABLE tb_user COMMENT &#39;用户信息表2&#39;;

3. Modify field comments

Modifying field comments is actually modifying the definition of the field.

ALTER TABLE tb_user MODIFY COLUMN name VARCHAR(30) NOT NULL COMMENT &#39;姓名2&#39;;

Note: When modifying, you must write the complete definition of the field, such as field type, attributes, etc. Never overwrite other attributes defined in this field just to modify a comment.

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4. Query field information

SHOW FULL COLUMNS FROM tb_user;

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