SQL select from data in query where this data is not already in the database?

Question

I want to check my database for records that I already have recorded before making a web service call.

Here is what I imagine the query to look like, I just can\'t

Answer 1

I would probably just do:

SELECT id
FROM table
WHERE id IN (1,2,3,4);

And then process the list of results, removing any returned by the query from your list of "records to submit".