PHP-从mySQL服务器检索数据

有人知道如何检索一段数据并在php文件中显示结果吗？ 我要输入的类似查询如下：

SELECT 'email' FROM 'users' WHERE 'username' = 'bob'

因此，结果将只是电子邮件

谢谢

Kevin要连接吗

$con = mysql_connect("host","userName","passWord");
if (!$con){die('Could not connect: ' . mysql_error());}
mysql_select_db("dbNameToSelect", $con);

质疑

$result = mysql_query("SELECT `email` FROM `users` WHERE `username` = 'bob'");
while($row = mysql_fetch_array($result)){
   // do stuff with $row['colName']
}

关闭连接

mysql\u close（$con）
以连接

$con = mysql_connect("host","userName","passWord");
if (!$con){die('Could not connect: ' . mysql_error());}
mysql_select_db("dbNameToSelect", $con);

质疑

$result = mysql_query("SELECT `email` FROM `users` WHERE `username` = 'bob'");
while($row = mysql_fetch_array($result)){
   // do stuff with $row['colName']
}

关闭连接
mysql\u close（$con）
另请参见：
有几个很好的例子参见：
有几个很好的例子
您需要连接数据库并从数据库中获取数据，比如mysql。检查以下代码：

$server = "localhost";
$username = "root";
$password = "";
$database = "mysampledb";

mysql_connect($server, $username, $password);
mysql_select_db($database);

$result = mysql_query("SELECT email FROM users WHERE username = 'bob'") or die(mysql_error());

while($row = mysql_fetch_assoc($result)) {
    echo $row["email"];
}

您需要从数据库（如mysql）连接和获取数据。检查以下代码：

$server = "localhost";
$username = "root";
$password = "";
$database = "mysampledb";

mysql_connect($server, $username, $password);
mysql_select_db($database);

$result = mysql_query("SELECT email FROM users WHERE username = 'bob'") or die(mysql_error());

while($row = mysql_fetch_assoc($result)) {
    echo $row["email"];
}

如何连接到数据库？如何连接到数据库？