PHP cannot connect to MySql database on live web server - php

Question

$con=mysqli_connect('localhost:3306','Punya','password','saain');
My PHP website, which is live is unable to connect to database. It works fine on my Pcs local server. When I write localhost:3306, it executes the echo statement I wrote for debugging.
If I write just localhost, it gives:
http 500 error
.

Answer 1

Cannot say much without knowing the actual error. But I could assume a few things based on what you have given.
When you pass localhost as the hostname to the mysqli_connect() function, it tries to create the connection using a Unix socket instead of TCP/IP. So it seems like either you don't have permissions to access the socket, or you need to get the correct socket information from your hosting provider.
Also, when you pass it as localhost:3306, you force it to connect via TCP/IP instead of socket. That's why it works.
However, you can force mysqli_connect() function to connect via TCP/IP by providing the hostname as 127.0.0.1.
$con = mysqli_connect('127.0.0.1','Punya','password','saain');
If this doesn't work, I assume they have defined a different default port for mysql in the php configuration. You can see it by printing it like:
echo ini_get("mysqli.default_port");
In case this default port is different from 3306 (which is unlikely), you can pass the port as the fifth paramter to mysqli_connect() function like this.
$con = mysqli_connect('127.0.0.1','Punya','password','saain', 3306);
You need to contact your hosting provider to get more details on this. Until you do that, your solution is to connect as shown above.
I hope you understand why it happens :) Feel free to ask if you have any doubts.

Answer 2

Try to check in
check here
Synax errors
check in your 👇
file.php

Answer 3

Check what version your live server is running and what version our location machine is running. most of the time environmental factors make these types of errors. I'm going to assume your hosting environment is a shared hosting for this answer
There are couple of things you can do identify the problem first.
Enable Errors
if you are hosted on a cPanel shared hosting server I doubt you can change the php.ini file. what you can do is enable PHP errors on runtime so you will have a proper error than just a 500 error. put the below codes in the top of your PHP file
<?php
error_reporting(E_ALL);
ini_set("display_errors", "On");
PHP info file
create a php.info file to identify what sort environment you are hosting your website on.
<?php
phpinfo();
?>
Cpanel has there own MYSQL server domain and port. this information you should get when you are creating a database in cPanel.
Once you have the error. paste it here we might be able to give you a better answer how to fix it