Error when connecting to MySQL using PHP/PDO

Question

My code was working all fine yesterday and today it suddenly just don't want to connect to my database. I have changed no settings on it or on the code and I haven't updated any software either. All I do is this:

new PDO('mysql:host=localhost;port=3306;dbname=test', 'username', 'password');

And I get a nice exception message saying this:

Warning: PDO::__construct(): [2002] No such file or directory (trying to connect via unix:///tmp/mysql.sock) in ...

The thing is: I'm clearly not trying to connect using a unix socket but using TCP/IP. What am I doing wrong? Is there something I'm missing here?

Thanks for any help.

Answer 1

You are using a Unix socket. When reading "localhost" MySQL client libraries don't interpret it as TCP host "localhost" and resolve that name but use the default Socket location. For using TCP on the local machine you have to use 127.0.0.1 as hostname.

To sepcify the past use unix_socketinstead of host in the DSN. The location of the socket used for localhost can be defined at compile time or in some versions of PHP using pdo_mysql.default_socket in the php.ini.