We use Harvest as our source control.  Our approach is as follows:

1. Developers develop code and place it in Harvest (Dev env.)
2. Code is migrated to Test and tested by QA team.  They also promote the code to Test env. in Harvest.
3. Developers build install BAT files that install into Dev|Test|Staging|Production env.  These are placed in Harvest and migrated the same as code.
4. After the install scripts are tested by Dev|Team members the code and install BATs are promoted to Staging (BTW install BATs use osql and produce error logs).
5. DBA examines the scripts/bat files for anything incorrect.  They then run the BAT file and report errors.
6. QA\UAT\performance testing is done in Staging with DBA assistance, Profiler, etc..
7. Code is promoted to Prod and DBA examines the BAT file and runs it, reports errors.

The process for DBA to install code (minus backups CYA) is about 15 - 30 minutes.  All code migrations are done this way and it proves to be quite handy.