


PHP uses PDO to operate MySQL database instance, pdomysql database instance_PHP tutorial
php uses PDO to operate MySQL database instance, pdomysql database instance
The example in this article describes the method of using PDO to operate the MySQL database in PHP. Share it with everyone for your reference. The specific analysis is as follows:
PDO is a common class for mysql database operations. We can directly use pdo to operate the database without customizing the class. However, pdo is not enabled in the default configuration of php, so we must enable it in php.ini first. Before it can be used, here is a detailed introduction.
The PDO extension defines a lightweight, consistent interface for PHP to access the database. It provides a data access abstraction layer so that no matter what database is used, queries and data can be obtained through consistent functions.
The PHP version supported by PDO is PHP5.1 and higher, and PDO is enabled by default under PHP5.2.
The following is the configuration of PDO in php.ini:
In order to enable support for a certain database, the corresponding extension needs to be turned on in the php configuration file. For example, to support MySQL, the following extension needs to be turned on:
Here is the use of PDO to perform basic add, delete, modify and query operations on mysql. The PHP program code is as follows:
$dsn="mysql:dbname=test;host=localhost";
$db_user='root';
$db_pass='admin';
try{
$pdo=new PDO($dsn,$db_user,$db_pass);
}catch(PDOException $e){
echo 'Database connection failed'.$e->getMessage();
}
//Add
$sql="insert into buyer (username,password,email) values ('ff','123456','admin@admin.com')";
$res=$pdo->exec($sql);
echo 'Number of lines affected:'.$res;
//Modify
$sql="update buyer set username='ff123' where id>3";
$res=$pdo->exec($sql);
echo 'Number of lines affected:'.$res;
//Query
$sql="select * from buyer";
$res=$pdo->query($sql);
foreach($res as $row){
echo $row['username'].'
';
}
//Delete
$sql="delete from buyer where id>5";
$res=$pdo->exec($sql);
echo 'Number of lines affected:'.$res;
I hope this article will be helpful to everyone’s PHP programming design.

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