php mysql PDO 查询操作的实例详解

php mysql PDO 查询操作的实例详解

<?php $dbh = new PDO('mysql:host=localhost;dbname=access_control', 'root', '');  $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);  $dbh->exec('set names utf8');  /*添加*/ //$sql = "INSERT INTO `user` SET `login`=:login AND `password`=:password";  $sql = "INSERT INTO `user` (`login` ,`password`)VALUES (:login, :password)"; $stmt = $dbh->prepare($sql); $stmt->execute(array(':login'=>'kevin2',':password'=>''));  echo $dbh->lastinsertid();  /*修改*/ $sql = "UPDATE `user` SET `password`=:password WHERE `user_id`=:userId";  $stmt = $dbh->prepare($sql);  $stmt->execute(array(':userId'=>'7', ':password'=>'4607e782c4d86fd5364d7e4508bb10d9'));  echo $stmt->rowCount();  /*删除*/ $sql = "DELETE FROM `user` WHERE `login` LIKE 'kevin_'"; //kevin%  $stmt = $dbh->prepare($sql);  $stmt->execute();  echo $stmt->rowCount();  /*查询*/ $login = 'kevin%';  $sql = "SELECT * FROM `user` WHERE `login` LIKE :login";  $stmt = $dbh->prepare($sql);  $stmt->execute(array(':login'=>$login));  while($row = $stmt->fetch(PDO::FETCH_ASSOC)){     print_r($row);  }  print_r( $stmt->fetchAll(PDO::FETCH_ASSOC));  ?> 

1 建立连接

<?php $dbh=newPDO('mysql:host=localhost;port=3306; dbname=test',$user,$pass,array( PDO::ATTR_PERSISTENT=>true )); ?> 

持久性链接PDO::ATTR_PERSISTENT=>true

2. 捕捉错误

<?php try{ $dbh=newPDO('mysql:host=localhost;dbname=test',$user,$pass);  $dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);  $dbh->exec("SET CHARACTER SET utf8"); $dbh=null; //断开连接 }catch(PDOException$e){ print"Error!:".$e->getMessage()."<br/>"; die(); } ?> 

3. 事务的

<?php try{ $dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);  $dbh->beginTransaction();//开启事务 $dbh->exec("insertintostaff(id,first,last)values(23,'Joe','Bloggs')"); $dbh->exec("insertintosalarychange(id,amount,changedate) values(23,50000,NOW())"); $dbh->commit();//提交事务  }catch(Exception$e){ $dbh->rollBack();//错误回滚 echo"Failed:".$e->getMessage(); } ?> 

4. 错误处理

a. 静默模式(默认模式)

$dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_SILENT); //不显示错误$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_WARNING);//显示警告错误，并继续执行$dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);//产生致命错误，PDOException

<?php try{    $dbh = new PDO($dsn, $user, $password);    $sql = 'Select * from city where CountryCode =:country';    $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_WARNING);    $stmt = $dbh->prepare($sql);    $stmt->bindParam(':country', $country, PDO::PARAM_STR);    $stmt->execute();    while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {     print $row['Name'] . "/t";    }  }  // if there is a problem we can handle it here  catch (PDOException $e) {    echo 'PDO Exception Caught. ';    echo 'Error with the database: <br />';    echo 'SQL Query: ', $sql;    echo 'Error: ' . $e->getMessage();  }  ?>