4.MySQL更新和删除数据

因为你呀，是我生命中那么亮那么亮的一缕光。——《云边有个小卖部》

1.MySQLi更新数据

用UPDATE

可修改数据库表中的数据

UPDATE table_name
SET column1=value, column2=value2,...
WHERE some_column=some_value

比如:

更新amiao这张表中的FirstName=‘Peter’ AND LastName='Griffin’这一行的age

mysqli_query($con,"UPDATE amiao SET Age=36 WHERE FirstName='Peter' AND LastName='Griffin'");

更新id=2的一堆内容

$sql = "update amiao set real_name ='aa', birthday = '2022-05-20' where id = 2";
$result = mysqli_query($conn,$sql);
if($result){
    
    echo "更新成功！";
}else{
    
    echo "更新失败！";
}

2.MySQLi删除数据

用DELETE
用于从数据库表中删除行

DELETE FROM table_name
WHERE some_column = some_value

比如:

删除amiao这个表里面的LastName=‘Griffin’

mysqli_query($con,"DELETE FROM amiao WHERE LastName='Griffin'");

删id<3的一堆内容

$sql = "delete from amiao where id < 3";
$result = mysqli_query($conn,$sql);
if($result){
    
    echo "删除成功！";
}else{
    
    echo "删除失败！";
}