mysqli_connect 没有连接到本地主机

Question

As title suggests, I'm getting the following error when using mysqli_connect:

Warning: mysqli_connect(): php_network_getaddresses: getaddrinfo failed: nodename nor servname provided, or not known in /Users/username/Sites/test.php on linez 2

Warning: mysqli_connect(): (HY000/2002): php_network_getaddresses: getaddrinfo failed: nodename nor servname provided, or not known in /Users/username/Sites/test.php on line 2 Could not connect:

<?php
$link = mysqli_connect(‘localhost’, ‘username’, ‘password’);
if (!$link) {
    die('Could not connect: ' . mysql_error());
}
echo 'Connected successfully';
mysql_close($link);
?>

My firewall is turned off and apache2 is turned on, I am able to view localhost/Username/Sites/test.php as well as logging into mysql using localhost.

Answer 1

from where you bring those quotes ? you should use single quotes.

try this:

    $link = mysqli_connect('localhost', 'username', 'password'); //you forgot the database

and why you mix between mysqli and mysql ?

Like that you connect to database:

 $link = mysqli_connect("localhost","username","password","database") or die("Error " . mysqli_error($link));

please read good the documentation here http://se2.php.net/mysqli_select_db

Answer 2

如果您使用的是 OS X 中内置的 textedit 应用程序，则从 TextEdit 的首选项窗格中禁用/取消选中名为“Smart Quotes”的功能，然后您将必须替换代码中的所有现有引号。

Answer 3

I have encountered this problem as well but none of the answers helped.

Despite what many answers say, the database name is not mandatory as a 4th parameter, as per the documentation: https://www.php.net/manual/en/mysqli.construct.php - all the parameters are optional.

For me what solved it was to double check the database host as in my code it is dynamic and it was picking up wrongly the distant database host instead of localhost.

$mysqli = IS_LOCAL ? 
    new mysqli($settings->localDBhost, $settings->localUser, $settings->localPassword)
    : new mysqli($settings->DBhost, $settings->DBuser, $settings->DBpassword);

(After I created a virtual host, I had to add it to the IS_LOCAL constant's condition)

Answer 4

$link = mysqli_connect(‘localhost’, ‘username’, ‘password’);

应该

$link = mysqli_connect(‘localhost’, ‘username’, ‘password’, 'yourdatabase');

Answer 5

Try:

$dbc = mysqli_connect('localhost', 'username', 'password', 'phonehome','3306','/Applications/XAMPP/xamppfiles/var/mysql/mysql.sock') OR die('Could not connect to database. Verify connection.php settings and SQL DB is running. Error: '.mysqli_connect_error());

Which is defining your Hostname, port, username, password, db and mySQL socket, it worked for me.

Answer 6

For some reason I can't remember (I think I read it somewhere else on SO, actually), when you connect to 'localhost' using mysqli(), you actually have to specify what port number you're connecting on as well:

$dbconn = new mysqli('localhost:3306', /*your username*/, /*your password*/, /*your database name*/);

3306 is, if I remember correctly, the default port, but even so you need to specify that in this case - literally only when you try to connect on localhost, but for some reason that's how it is.

Also - I noticed that in your original code your quotation marks in your mysqli_connect(...) line look different from those in your other code lines. This may just be something that happened in stack overflow when you wrote out your question, but if it's not and those different quotation marks are in your code as well, then you may need to change them to the same ones as in your later code.