Two controversial questions in one!
1. Are SQL questions allowed here?
https://dba.stackexchange.com/help/on-topic says:
dba.se is for those needing expert answers to advanced database-related questions concerning traditional SQL RDBMS and NoSQL alternatives.
If you have a question about...
- Advanced Querying including window-functions, dynamic-sql, and query-performance
…then you're in the right place to ask your question!
but, dba.se is not the right place to ask questions about...
So basic SQL questions are not on-topic, but advanced ones are. See the related questions sidebar for past discussions on this point.
2. Should questions be migrated?
Assuming the question is off-topic, the question is then whether you should vote to migrate or close as off-topic.
My personal view is that most of the time migration is counter-productive. The question author tends not to wait for migration to complete and copies the question to Stack Overflow. If migration is successful, there are then two copies of the same question, which requires effort to combine. Close review can take quite a while on dba.se these days.
There is an argument that migration is useful when it helps the question author navigate the Stack Exchange ecosystem, but I am not particularly persuaded. It's not so difficult to copy-and-paste a question to the site it should have been asked on in the first place.
My own personal bar for migration is quite high. The question needs to be obviously off-topic here, on-topic at the target site, and complete enough that it is unlikely to be closed at the destination (as that would return the question here).