Question: How do you manage version control?

Hello,
So we've been reviewing our processes and working on improving them. One
area we've been lacking is a procedure to version control our database
functions, table changes, static data etc.

I'm curious how others do it. Ideally, we want it to be part of our release
/ build process so that we deploy functions.

However, how do you handle dependancies?

We've also used patch files if we need to modify tables - these are
typically written to only run once, ie alter table add column x int. Any
thoughts on putting this in to a process so that it can be run mutliple
times without any issue?

Thanks,
Bryan.