Example sharing of using PDO to operate MySQL database (collection)
The following editor will bring you a basic tutorial on operating MySQL with PDO (recommended). The editor thinks it’s pretty good, so I’ll share it with you now and give it as a reference. Let’s follow the editor to take a look.
The PDO extension in PHP defines a lightweight, consistent interface for PHP to access the database. It provides a data access abstraction layer, so that no matter what is used Databases can perform queries and obtain data through consistent functions.
The PHP version supported by PDO is PHP5.1 and higher, and under PHP5.2 PDO is enabled by default.
The following is in php. PDO configuration in ini:
extension=php_pdo.dll
In order to enable support for a certain database, the corresponding extension needs to be opened in the php configuration file, for example To support MySQL, you need to enable the following extension
extension=php_pdo_mysql.dll
The following is the use of PDO to perform basic add, delete, modify and query operations on mysql
Create a test database, and then run the following SQL statement:
##
DROP TABLE IF EXISTS `test`; CREATE TABLE `test` ( `id` int(10) NOT NULL DEFAULT '0', `user` char(20) DEFAULT NULL, PRIMARY KEY (`id`), KEY `idx_age` (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Program code:
<?php header("content-type:text/html;charset=utf-8"); $dsn="mysql:dbname=test;host=localhost"; $db_user='root'; $db_pass='admin123'; try{ $pdo=new PDO($dsn,$db_user,$db_pass); }catch(PDOException $e){ echo '数据库连接失败'.$e->getMessage(); } //新增 $sql="insert into test (id,user) values (1,'phpthinking')"; $res=$pdo->exec($sql); echo '影响行数:'.$res; //修改 $sql="update test set user='phpthinking' where id=1"; $res=$pdo->exec($sql); echo '影响行数:'.$res; //查询 $sql="select * from test"; $res=$pdo->query($sql); foreach($res as $row){ echo $row['user'].'<br/>'; } //删除 $sql="delete from test where id=1"; $res=$pdo->exec($sql); echo '影响行数:'.$res;
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