Slava Murygin shows various ways to filter data, in particular data from fn_dblog():
Would say we need to extract an information associated with an “UPDATE” for LSNs started at “0000004f:00000087:0001”. You can just specify Starting and Ending LSNs as “fn_dblog” parameters:
[…]
That portion of code would return you ONLY Log records between LSNs “0000004f:00000087:0001″ and “0000004f:00000088:0001″.
Slava’s post uses fn_dblog() as an example but the techniques are applicable across the board, and in practice sum up to “get the fewest number of rows and fewest number of columns you need to solve the problem at hand.”