[dba-SQLServer] Constant Poll: Approaches

I have a pair of tables, call them Fiction and Fact. People around the world
enter rows into Fiction. The database has to process these records and
depending on some logic, it makes a decision whether or not to enter a
similar row into Fact. The logic is not important to my question. What I'm
trying to do is set up a "polling" system so that the engine will examine
the Fiction table every 10 seconds or so and if there are any new rows, fire
the logic that decides whether to create a row in the Fact table, and then
timestamp the Fiction row so we know that it's been processed.

One important detail in this operation is that I cannot move to row 2 before
completely processing row 1, because the results of row 1 may affect the
outcome of row 2.

I can think of a couple of approaches -- agent job, trigger, proc with an
infinite loop. But before I get started coding this, I thought that I'd
reach out and see if anyone's done something similar and has advice on which
approach might be best.

Thanks in advance for any suggestions.

Arthur