php mysql连接方式pdo用法详解

2. $dbh = new PDO('mysql:host=localhost;dbname=access_control', 'root', '');
3. $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
4. $dbh->exec('set names utf8');
5. /*添加*/
6. //$sql = "INSERT INTO `user` SET `login`=:login AND `password`=:password";
7. $sql = "INSERT INTO `user` (`login` ,`password`)VALUES (:login, :password)"; $stmt = $dbh->prepare($sql); $stmt->execute(array(':login'=>'kevin2',':password'=>''));
8. echo $dbh->lastinsertid();
9. /*修改*/
10. $sql = "UPDATE `user` SET `password`=:password WHERE `user_id`=:userId";
11. $stmt = $dbh->prepare($sql);
12. $stmt->execute(array(':userId'=>'7', ':password'=>'4607e782c4d86fd5364d7e4508bb10d9'));
13. echo $stmt->rowCount();
14. /*删除*/
15. $sql = "DELETE FROM `user` WHERE `login` LIKE 'kevin_'"; //kevin%
16. $stmt = $dbh->prepare($sql);
17. $stmt->execute();
18. echo $stmt->rowCount();
19. /*查询*/
20. $login = 'kevin%';
21. $sql = "SELECT * FROM `user` WHERE `login` LIKE :login";
22. $stmt = $dbh->prepare($sql);
23. $stmt->execute(array(':login'=>$login));
24. while($row = $stmt->fetch(PDO::FETCH_ASSOC)){
25. print_r($row);
26. }
27. print_r( $stmt->fetchAll(PDO::FETCH_ASSOC));
28. ?>

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1、建立连接

2. $dbh=newPDO('mysql:host=localhost;port=3306; dbname=test',$user,$pass,array(
3. PDO::ATTR_PERSISTENT=>true
4. ));
5. ?>

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持久性链接PDO::ATTR_PERSISTENT=>true

2，捕捉错误

2. try{
3. $dbh=newPDO('mysql:host=localhost;dbname=test',$user,$pass);
4. $dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
5. $dbh->exec("SET CHARACTER SET utf8");
6. $dbh=null; //断开连接
7. }catch(PDOException$e){
8. print"Error!:".$e->getMessage()."
   ";
9. die();
10. }
11. ?>

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3，pdo事务

2. try{
3. $dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
4. $dbh->beginTransaction();//开启事务
5. $dbh->exec("insertintostaff(id,first,last)values(23,'Joe','Bloggs')");
6. $dbh->exec("insertintosalarychange(id,amount,changedate)
7. values(23,50000,NOW())");
8. $dbh->commit();//提交事务
9. }catch(Exception$e){
10. $dbh->rollBack();//错误回滚
11. echo"Failed:".$e->getMessage();
12. }
13. ?>

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4. 错误处理 a. 静默模式(默认模式)

2. try{
3. $dbh = new PDO($dsn, $user, $password);
4. $sql = 'Select * from city where CountryCode =:country';
5. $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_WARNING);
6. $stmt = $dbh->prepare($sql);
7. $stmt->bindParam(':country', $country, PDO::PARAM_STR);
8. $stmt->execute();
9. while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
10. print $row['Name'] . "/t";
11. }
12. } // if there is a problem we can handle it here
13. catch (PDOException $e) {
14. echo 'PDO Exception Caught. ';
15. echo 'Error with the database:
    ';
16. echo 'SQL Query: ', $sql;
17. echo 'Error: ' . $e->getMessage();
18. }
19. ?>

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1，使用 query()

2. $dbh->query($sql); 当$sql 中变量可以用$dbh->quote($params); //转义字符串的数据
3. $sql = 'Select * from city where CountryCode ='.$dbh->quote($country);
4. foreach ($dbh->query($sql) as $row) {
5. print $row['Name'] . "/t";
6. print $row['CountryCode'] . "/t";
7. print $row['Population'] . "/n";
8. }
9. ?>

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2，使用 prepare, bindParam和 execute [建议用,同时可以用添加、修改、删除]

2. $dbh->prepare($sql); 产生了个PDOStatement对象
3. PDOStatement->bindParam()
4. PDOStatement->execute();//可以在这里放绑定的相应变量
5. ?>

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3、php pdo事务例子

2. try {
3. $dbh = new PDO('mysql:host=localhost;dbname=test', 'root', '');
4. $dbh->query('set names utf8;');
5. $dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
6. $dbh->beginTransaction();
7. $dbh->exec("Insert INTO `test`.`table` (`name` ,`age`)VALUES ('mick', 22);");
8. $dbh->exec("Insert INTO `test`.`table` (`name` ,`age`)VALUES ('lily', 29);");
9. $dbh->exec("Insert INTO `test`.`table` (`name` ,`age`)VALUES ('susan', 21);");
10. $dbh->commit();
11. } catch (Exception $e) {
12. $dbh->rollBack();
13. echo "Failed: " . $e->getMessage();
14. }
15. ?>

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