SELECT platform, channel, COUNT(DISTINCT(platformUserId)) as cnt FROM( SELECT platform, channel, platformUserId, MIN(insertTimestamp) as rtime FROM tsz_user GROUP BY platform, channel, platformUserId ) a where a.rtime >= 1392393600 and a.rtime < 1392480000 GROUP BY platform, channel; |
耗时2分33秒
SELECT platform, channel, COUNT(DISTINCT(platformUserId)) as cnt FROM( SELECT platform, channel, platformUserId, MIN(insertTimestamp) as rtime FROM tsz_user GROUP BY platform, channel, platformUserId order by null ) a where a.rtime >= 1392393600 and a.rtime < 1392480000 GROUP BY platform, channel order by null; |
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