If you haven't already put alot of work into your database yet, then you would probably be best off just starting over with a fresh database. You can always copy in your player-related tables later if needed. Judging by the different errors you have gotten and different things it sounds like you have done, I have no idea what state your current database may be in. Did you back up your database before hand? As long as you have a backup, you can always source that back in to replace anything that has changed. Then you will just need to run any needed SQL changes from the source code to get it updated to run with the version of server code you are wanting to run.
First off, you need to figure out exactly what versions of Database and Server code you are running. Post that here and maybe we can help you. Otherwise, it seems like you may have been making things worse and not easily recoverable. Really, someone with more database experience than I would be better to help with this though, so don't take everything I say as a fact
If you are running a PEQ database, it should be fairly easy to get things going once you have matching versions of database and server code. I think the PEQ forums probably have more information on that subject than you will find here though.