我有一个配置单元表,其中包含形式的事务数据(高度简化)
id Status Value UpdatedTimeStamp
515 Open 1 2014-05-08T11:43:27
516 Open NULL 2014-05-08T11:43:27
515 Answered 1 2014-05-09T11:43:27
515 Closed NULL 2014-05-10T11:43:27
517 Open NULL 2014-05-09T11:43:27
516 Closed NULL 2014-05-09T11:43:27
对于我的用例,我需要一个包含唯一id的输出表,当按时间戳排序时,列条目是该列中该特定id的最后一个非NULL值。
因此,所需输出为:
id Status Value UpdatedTimeStamp
515 Closed 1 2014-05-10T11:43:27
516 Closed NULL 2014-05-09T11:43:27
517 Open NULL 2014-05-09T11:43:27
我正试图通过在分区上使用窗口功能来实现这一点
INSERT OVERWRITE TABLE testSample2 SELECT id, FIRST_VALUE (Status) OVER SortedData, FIRST_VALUE (Value IGNORE NULLS) OVER SortedData, FIRST_VALUE (UpdatedTimeStamp) OVER SortedData FROM testSample WINDOW SortedData (PARTITION BY id ORDER BY UpdatedTimeStamp DESC ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING);
这给了我NullPointerException(可能,配置单元中还不支持IGNORE NULLS)。请建议我如何取最后一个非NULL值。
尝试使用类似的东西:
select ss.vl1, FIRST_VALUE(ss.ky) OVER (PARTITION BY ss.vl1 ORDER BY ss.nl, ss.vl rows unbounded preceding)
FROM (
SELECT IF(s.vl=123456, 'sasa', 'AAAAAA') as vl1, s.vl, s.ky, IF(s.ky IS NULL, 1, 0) as nl
FROM (
select explode(map(NULL, 123, 1, 1234, 2, 12345, 3, 123456)) as (ky, vl) from default.dual) s ) ss;
vl1 _wcol0
AAAAAA 1
AAAAAA 1
AAAAAA 1
sasa 3