How to modify field type in MySQL?

In MySQL, you can modify the data type of a field in the table through the alter table statement. The following article will take you through the alter table statement and introduce how to modify the field type. I hope it will be helpful to you.

In MySQL, the alter table statement is used to add, modify, or delete columns (fields) in an existing table.

1. Add a field (column)

alter table 表名 add 字段名 数据类型

Example: Add a field named The new column of "Birthday", the data type is "date"

alter table Persons add Birthday date

Description: The type of the new column "Birthday" is date, which can store dates

2. Modification Field name

alter table 表名 rename column A to B

3. Modify field type

alter table 表名 alter column 字段名 数据类型

Example: Change the table" The data type of the "Birthday" column in Persons" is changed to "year"

alter table Persons alter column Birthday year

Explanation: The data type of the "Birthday" column is year, which can store the year in 2-digit or 4-digit format.

4. Delete fields

alter table 表名 drop column 字段名

Example:Delete the "Birthday" column in the "Person" table

alter table Persons drop column Birthday

Related video tutorial recommendations: "MySQL Tutorial"

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