Home Database Mysql Tutorial How to add comments when creating a table in MySQL

How to add comments when creating a table in MySQL

Jan 05, 2022 pm 03:11 PM
mysql Comment

In mysql, you can use the "create table" statement and the comment keyword to add comments when creating a table. The syntax is "create table table name (field name field type comment 'field comment') comment=' Table comment ';'.

How to add comments when creating a table in MySQL

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

In the MySQL database, comments on tables or fields (columns) are added using the attribute comment.

In the script that creates a new table, you can add comments by adding the comment attribute in the field definition script.

MySQL table creation statement adding comments

1. Table creation comments

Syntax:

create table 表名 ( 
    字段名 字段类型 comment '字段的注释'
) comment='表注释';
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Example

CREATE TABLE student(
  id INT PRIMARY KEY AUTO_INCREMENT COMMENT '学号',
  name VARCHAR(200) COMMENT '姓名',
  age    int COMMENT '年龄'
) COMMENT='学生信息'
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2. Modify comments

Modify table comments-ALTER TABLE student COMMENT 'Student table';

Modify column comments-ALTER TABLE student MODIFY COLUMN name VARCHAR(100) COMMENT 'name';

SELECT table_name,table_comment FROM information_schema.tables  WHERE table_schema = '所在的db' AND table_name ='表名groups'
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SHOW FULL COLUMNS FROM groups
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-- This can be used to search for a name or a certain name based on conditions Data type column information: for example

SHOW FULL COLUMNS FROM tableName WHERE FIELD = 'add_time' OR TYPE LIKE '%date%' -- 查看tableName表中列名是add_time的或类型是date的列
SELECT  column_name, column_comment FROM information_schema.columns WHERE table_schema ='db'  AND table_name = 'groups'
SHOW  CREATE TABLE communication_group
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