PHP database operations--data preprocessing, update, delete

Statement preprocessing: Generally speaking, it is a query and multiple executions. It will be often used in our later projects.

Creation:

//Creation preprocessing

$createinto=$connent->prepare("insert into zh(name,age,email) values (?,?,?)");

sql statement, the parameters use? instead of reserved

//绑定  
$createinto->bind_param("sis",$name,$age,$email);

The binding parameter s is String type i is int type

$name="zhanghao1";  
$age=1;  
$email="1234123123@qq.com";  
$createinto->execute();  
  
$name="zhanghao2";  
$age=2;  
$email="1234123123@qq.com";  
$createinto->execute();

Execute the statement; finally the data is inserted successfully. (The premise is to connect to the database and use)

Delete the specified entry:

mysqli_query($connent,"delete from zh where name='zhanghao1'");

Delete the entire table data without adding where conditions

Update the specified entry:

mysqli_query($connent,"update zh set age=3 where name='zhanghao2'");

Modify zhanghao2’s age to 3

Close the database after all database operations are completed.

----Complete code-------

connect_error){  
    die("连接失败: " . $connent->connect_error);  
}else{  
    echo "成功";  
  
}  
//创建预处理  
$createinto=$connent->prepare("insert into zh(name,age,email) values (?,?,?)");  
  
//绑定  
$createinto->bind_param("sis",$name,$age,$email);  
//多次执行  
$name="zhanghao1";  
$age=1;  
$email="1234123123@qq.com";  
$createinto->execute();  
  
$name="zhanghao2";  
$age=2;  
$email="1234123123@qq.com";  
$createinto->execute();  
echo "插入成功";  
  
//删除数据 删除表中 name为zhanghao1的数据  
mysqli_query($connent,"delete from zh where name='zhanghao1'");  
  
mysqli_query($connent,"update zh set age=3 where name='zhanghao2'");  
  
$connent->close();  
?>

We can find that where is the basis for judging conditions. According to it, we can conditionally query, Condition deletion and condition modification.