Not exactly Clojure-specific, hope that's alright :-) I have a table b that's effectively an exclusion filter for another table a, so it's storing the primary key of rows that I want to exclude. Upon selection from a, I want to update b with the primary key from the retrieved rows, but I also want to return the rows from a. With Postgres I can do something like

INSERT INTO b
SELECT id FROM a LEFT JOIN b ON a.id=b.id WHERE b.id IS NULL
RETURNING *

WITH ins(id) AS ( [stmt above ] ) SELECT ins.id, ... FROM ins JOIN a on a.id=ins.id