记录一下PHP连接MySQL的两种方式。

先mock一下数据，可以执行一下sql。

/*创建数据库*/CREATE DATABASE IF NOT EXISTS `test`;/*选择数据库*/USE `test`;/*创建表*/CREATE TABLE IF NOT EXISTS `user` (    name varchar(50),    age int);/*插入测试数据*/INSERT INTO `user` (name, age) VALUES('harry', 20), ('tony', 23), ('harry', 24);

第一种是使用PHP原生的方式去连接数据库。代码如下：

<?php$host = 'localhost';$database = 'test';$username = 'root';$passWord = 'root';$selectName = 'harry';//要查找的用户名，一般是用户输入的信息$insertName = 'testname';$connection = mysql_connect($host, $username, $password);//连接到数据库mysql_query("set names 'utf8'");//编码转化if (!$connection) {    die("could not connect to the database.\n" . mysql_error());//诊断连接错误}$selectedDb = mysql_select_db($database);//选择数据库if (!$selectedDb) {    die("could not to the database\n" . mysql_error());}$selectName = mysql_real_escape_string($selectName);//防止SQL注入$query = "select * from user where name = '$selectName'";//构建查询语句$result = mysql_query($query);//执行查询if (!$result) {    die("could not to the database\n" . mysql_error());}while ($row = mysql_fetch_row($result)) {    //取出结果并显示    $name = $row[0];    $age = $row[1];    echo "Name: $name Age: $age \n";}//添加记录$insertName = mysql_real_escape_string($insertName);//防止SQL注入$insertSql = "insert into user(name, age) values('$insertName', 18)";$result = mysql_query($insertSql);echo $result . "\n";//更新记录$updateSql = "update user set age = 19 where name='$insertName'";$result = mysql_query($updateSql);echo $result . "\n";//删除记录$deleteSql = "delete from user where age = 19";$result = mysql_query($deleteSql);echo $result . "\n";mysql_close($connection);//关闭连接

其运行结构如下：

Name: harry Age: 20 Name: harry Age: 24 111

第二种是使用PDO的方式去连接数据库，代码如下：

<?php$host = 'localhost';$database = 'test';$username = 'root';$password = 'root';$selectName = 'harry';//要查找的用户名，一般是用户输入的信息$insertName = 'testname';$pdo = new PDO("mysql:host=$host;dbname=$database", $username, $password);//创建一个pdo对象$pdo->exec("set names 'utf8'");$sql = "select * from user where name = ?";$stmt = $pdo->PRepare($sql);$rs = $stmt->execute(array($selectName));if ($rs) {    // PDO::FETCH_ASSOC 关联数组形式    // PDO::FETCH_NUM 数字索引数组形式    while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {        $name = $row['name'];        $age = $row['age'];        echo "Name: $name Age: $age \n";    }}$oldAge = 18;$insert = $pdo->prepare('insert into user(name, age) values(:name, :age)');$insert->bindParam(':name', $insertName, PDO::PARAM_STR);$insert->bindParam(':age', $oldAge, PDO::PARAM_INT);$result = $insert->execute();echo $result . "\n";$newAge = 19;$update = $pdo->prepare('update user set age = ? where name = ?');$update->bindParam(1, $newAge, PDO::PARAM_INT);$update->bindParam(2, $insertName, PDO::PARAM_STR);$result = $update->execute();echo $result . "\n";$delete = $pdo->prepare('delete from user where age = ?');$result = $delete->execute(array($newAge));echo $result . "\n";$pdo = null;//关闭连接

其结果与第一种相同。