gistfile1.sql

/*Selects all contracts, which aren't billed yet*/

SET @start_date = '2010-06-01', @end_date = '2010-06-30'; 
SET @month = MONTH(CURDATE()), @year = YEAR(CURDATE());
SELECT c.id, c.start_date, c.end_date, IF(tmp.id IS NULL, 'Billable', 'Not Billable')
FROM contracts c
LEFT JOIN (
	SELECT r.id, r.contract_id
	FROM receivables r LEFT JOIN billing_cycles b ON r.billing_cycle_id = b.id
	WHERE b.month = @month AND b.year = @year
) tmp ON c.id = tmp.contract_id
WHERE (@start_date BETWEEN c.start_date AND c.end_date) OR 
      (c.start_date BETWEEN @start_date AND @end_date);