选择每日最新条目和相应数据

Question

我在SQLite中有一个表:

CREATE TABLE test_results(timestamp TEXT, npass INTEGER, nfails INTEGER)

我想返回每天的最后一次通过/失败信息.例如,如果表包含...

2009-08-31 23:30:19|0|24
2009-08-31 23:37:18|0|24
2009-08-31 23:40:00|0|24
2009-09-01 19:02:13|0|2
2009-09-01 19:08:24|2|0
2009-09-01 19:20:29|2|0

我想要一个选择声明返回...

2009-08-31 23:40:00|0|24
2009-09-01 19:20:29|2|0

提前致谢!

Answer 1

尝试:

SELECT t.timestamp,
       t.npass,
       t.nfails
  FROM TEST_RESULTS t
  JOIN (SELECT MAX(tt.timestamp) 'maxtimestamp'
         FROM TEST_RESULTS tt
     GROUP BY date(tt.timestamp)) m ON m.maxtimestamp = t.timestamp