I had an error (related to Date module I think? Can't remember.) on my site so I tried to do an update. Caused a WSOD so I svn reverted. Didn't help. Manually disabled each module in the database. Didn't help. Fixed some permissions. Helped... sort of.
Now I get this:
Drupal already installed To start over, you must empty your existing database. To install to a different database, edit the appropriate settings.php file in the sites folder. To upgrade an existing installation, proceed to the update script. View your existing site.
Running the upgrade script gives this error:
PDOException: SQLSTATE[HY000]  Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2) in drupal_get_installed_schema_version() (line 150 of /public_html/includes/install.inc).
Any other page redirects back to install.php.
So it seems like it can see the database to know that it's not empty, but can't really connect to it... what does this mean? What do I do about it.