Query tuning, indexing should be done at least once at dev, at QA before pushing to production environment. The execution plan should be evaluated. If you are serious, you can run Borland stress test in QA to generate traffic effect. It will than be continuous maintained/modified by Production DBA once pushed in production environment. There will be times Production DBA will push code back into development cycle. I have done both roles. "Development DBA bridges developers and DBAs, has to know both sides of work, can slip on either hat". Development DBAs have strength in coding and strength in knowing DB engine. Production DBAs know DB engine and network, storage related issues. Production DBA likely gets rotation schedule of 24x7. Development DBA protects us from falling into a design trap that will causes grief later in production (not bugs, QA dept handles bugs), and saves Developer and DBA arguments back-and-forth.