I think the answer was pretty clear in the question ["Where do SQL questions belong?"][4]:

> The way I see it:  
> 
>  - SQL *language* questions belong on [StackOverflow][1]  
>  - Database *server* questions belong on [ServerFault][2]  
>  - Database *tuning* questions belong on [dba.SE][3]

  [1]: https://stackoverflow.com/
  [2]: https://serverfault.com/
  [3]: https://dba.stackexchange.com/
  [4]: http://meta.serverfault.com/questions/1330/where-do-sql-questions-belong/1331#1331