How to update table data in MySQL database-Mysql Tutorial-php.cn

This article mainly takes you to understand and use theMySQL Updatestatement to update existing records in the database table.

Basic syntax of the Update statement:

UPDATE <表名> SET 字段 1=值 1 [,字段 2=值 2… ] [WHERE 子句 ] [ORDER BY 子句] [LIMIT 子句]

Copy after login

SETclause: used to specify the column name and column value to be modified in the table. Among them, each specified column value can be an expression or the default value corresponding to the column. If a default value is specified, the column value can be represented by the keyword DEFAULT.
WHEREClause: Optional. Used to limit the rows in the table to be modified. If not specified, all rows in the table will be modified.
ORDER BYclause: optional. Used to limit the order in which rows in a table are modified.
LIMITclause: optional. Used to limit the number of rows that are modified.

First, create a new database:

CREATE TABLE tasks ( id INT NOT NULL, subject VARCHAR(45) NULL, start_date DATE NULL, end_date DATE NULL )charset utf8;

Copy after login

Secondly, insert data:

insert into tasks values(1,'math',2029-6-1,2060-6-1)

Copy after login

Finally, update the data:

UPDATE `tasks` SET `start_date`='2029-6-1', `end_date`='2060-6-1' WHERE (`id`='1') AND (`subject`='math') AND (`start_date`='0000-00-00') AND (`end_date`='0000-00-00') LIMIT 1

Copy after login

Note: Ensure thatUpdateends with aWHEREclause, passed # The ##WHEREclause specifies the conditions that the updated records need to meet. If theWHEREclause is ignored,MySQLwill update all rows in the table.

mysql tutorial

The above is the detailed content of How to update table data in MySQL database. For more information, please follow other related articles on the PHP Chinese website!

Related labels：

mysql update

source：php.cn

Previous article：How to modify the table structure of MySQL database Next article：How to create a new table in MySQL database

Statement of this Website

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn