解答
183
SQL文(クエリ)
WITH master AS (
SELECT
cid
, session_count
, COUNT(*) AS pv
FROM
sample.web_log
GROUP BY
cid
, session_count
)
SELECT
ROUND(pageviews / sessions, 1) AS pv_per_session
FROM
(
SELECT
(
SELECT
SUM(pv) AS pageviews
FROM
master
) AS pageviews
, (
SELECT
COUNT(*)
FROM
master
) AS sessions
)



