Is there a better way of using SQL (mysql) to aggregate by 6 month windows? This seems to perform okay gets the relevant data in the normal case, but is obviously limited.
SELECT SUM(...) some_aggg,
(CASE
WHEN SOME_DATE > DATE_SUB(now(), INTERVAL 6 MONTH) THEN 3
WHEN SOME_DATE > DATE_SUB(now(), INTERVAL 12 MONTH) THEN 2
WHEN SOME_DATE > DATE_SUB(now(), INTERVAL 18 MONTH) THEN 1
ELSE 0
END) RECENCY
WHERE ...
GROUP BY RECENCY
ORDER BY RECENCY DESC