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HomeDatabaseMysql Tutorialmysql更新数据之update set用法

在mysql中更新数据是非常简单的一件事情,直接使用update set即可完成数据的更新了,下面我来给大家详细的介绍mysql中update set语句的用法。

update语法

 代码如下 复制代码

UPDATE [LOW_PRIORITY] [IGNORE] tbl_name
    SET col_name1=expr1 [, col_name2=expr2 ...]
    [WHERE where_definition]
    [ORDER BY ...]
    [LIMIT row_count]

实例

 代码如下 复制代码

create table links (name varchar(255) not null default '', url varchar(255) not null default '');

我们先随便插入一些数据

 代码如下 复制代码

INSERT INTO users(name, age) VALUES('姚明', 25), ('比尔.盖茨', 50), ('火星人', 600);

更新所有记录

 代码如下 复制代码

update links set url='http://www.hzhuti.com';

上面更新就是把整个数据表里url的值都埴写为了了,这样肯定不适合现在代数据开发了,

 代码如下 复制代码


update user set Password = password('123456') where User = 'root';

上面就可以根据条件进行一些数据的更新了,这样我们可以根据后面where条件来进行更新了。


下面分享一个php来更新mysql数据库中指定记录的方法

 代码如下 复制代码

$con = mysql_connect("localhost","peter","abc123");
if (!$con)
{
  die('Could not connect: ' . mysql_error());
}
mysql_select_db("my_db", $con);
mysql_query("UPDATE Persons SET Age = '36'
WHERE FirstName = 'Peter' AND LastName = 'Griffin'");
mysql_close($con);
?>

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