For a large software project recently, I was really out of my depth. And I did actually know this; and that the only reason I was employed was mostly a lack of other qualified candidates.

The job was to build a large application on top of PHP/MySQL, a system I had little experience with. (I did advise the employer of this beforehand -- I've been spoiled by C# ASP.NET/MVC and MSSQL Server) The main reason I applied was location, location, location -- on campus jobs which actually have any programming component are relatively rare.

For almost a year and a half I've slogged through this, and I think I can say I know (at least somewhat) what I'm doing now. I've made some mistakes, torn out some hair, and moved on. (I'm still working on this system nowadays, but I no longer feel completely lost)

In the future though, I'd like to keep my personal and professional self a little healthier than what occurred in this case.

So I'm curious -- what's the best way to handle a situation like this?