SELECT '[0-5>' AS bin,
SUM(duration <= 300) AS total
FROM Sessions
UNION ALL
SELECT '[5-10>' AS bin,
SUM(
duration > 300
AND duration <= 600
) AS total
FROM Sessions
UNION ALL
SELECT '[10-15>' AS bin,
SUM(
duration > 600
AND duration <= 900
) AS total
FROM Sessions
UNION ALL
SELECT '15 or more' AS bin,
SUM(duration > 900) AS total
FROM Sessions