连接到MySql DB（PHP）时遇到麻烦

Question

I have the following PHP code to connect to my db:

<?php
ob_start();
$host="localhost"; // Host name
$username="root"; // Mysql username
$password=""; // Mysql password
$db_name="test"; // Database name
$tbl_name="members"; // Table name

// Connect to server and select databse.
mysql_connect("$host", "$username", "$password")or die("cannot connect");

?>

However, I get the following error:

Warning: mysql_connect() [function.mysql-connect]: [2002] A 
connection attempt failed because the connected party did not (trying 
to connect via tcp://localhost:3306) in C:\Program Files (x86)\EasyPHP-
5.3.2i\www\checklogin.php on line 11

Warning: mysql_connect() [function.mysql-connect]: A connection 
attempt failed because the connected party did not properly respond 
after a period of time, or established connection failed because 
connected host has failed to respond. in C:\Program Files (x86)\EasyPHP-
5.3.2i\www\checklogin.php on line 11

Fatal error: Maximum execution time of 30 seconds exceeded in 
C:\Program Files (x86)\EasyPHP-5.3.2i\www\checklogin.php on line 11

I am able to add a db/tables via phpmyadmin but I can't connect using PHP.

Here is a screenshot of my phpmyadmin page: What could be the problem?

Answer 1

Check the following:

1. Is MySQL running?
2. Is there any firewall that could be blocking your computer from accepting connections to MySQL on port 3306?
3. Is MySQL listening on port 3306, or did it get changed to something nonstandard?
4. An odd one, but try changing from localhost to 127.0.0.1

Basically, the errors you're getting mean that it cannot connect to the server. It sends request to localhost:3306 , and only waits so long for a reply. it's not getting it, which means the request is either blocked (firewall) or ignored (MySQL is not running and/or is listening on a different port)

If phpMyAdmin came with the MySQL install, then it could be that it was configured to use the appropriately different port

Answer 2

ha i also had that issue now i fix it by changing port number eg "find.db.13344.hostedfind.com:3306". before it my connection was trying to access the "find.db.13344.hostedfind.com:3307" so it gave me this error Warning: mysql_connect() [function.mysql-connect]: [2002] A connection attempt failed because the connected party did not (trying to connect via tcp://localhost:3306) .

Answer 3

I also have noticed this issue linux version of xampp with MySSQL 5.6.12-log running over network. Also, a question asked in MySQL forum ( http://forums.mysql.com/read.php?52,294772,294772 ) resembles this, but not satisfactorily answered.

What I have noticed is, it is probably due to Networking being unstable, or too many mysql connections from other developers in the network connecting to the database server at the same time - and keeping the port number busy for a fraction of time. It is not often related to the configured connection time, nor maximum execution time, nor wrong username/password etc.

Amazingly, the same script, same password, and same network allows the same server run properly on the second attempt - without having to do anything as a fix.

Hence, it should be your momentarily unstable network fluctuation (or busy mysql connections), that goes on and off, and your script attempted to connect to the server when network was down for a very short time.

That is a guessed answer from personal experience related to this error, may not be exact.

But if the error message is persistent, you should really need to do something.

Answer 4

Maybe your MySQL is not using TCP for localhost. Please try

$host='/tmp/mysql.sock';

or whatever socket it might be using.