我有一个数据集，我需要标记这些调用，如字段Call_CA中所示，在SQL（Hive）中具有此条件。
在同一电话号码中，对于在呼叫CA之前拨打到其他LOB的呼叫，请将这些呼叫标记为BEFORE。对于在调用CA后拨打到其他LOB的呼叫，将这些呼叫标记为AFTER。
请您告诉我怎么做？
感谢大家的帮助。
gen_source_address Called_Time LOB Call_CA
2012123923 3/20/2015 18:10:00 ca
2012123923 3/20/2015 18:15:00 cl After
2012123923 4/20/2015 11:30:00 ca
2012123923 4/20/2015 11:31:00 ca
2012123923 4/20/2015 11:39:00 cl After
2012123923 4/20/2015 15:36:00 cl After
2012123923 4/27/2015 12:40:00 cl After
2012123923 4/28/2015 10:07:00 cl After
2012123923 4/28/2015 11:58:00 cl After
2012136626 1/10/2015 16:02:00 ca
2012146914 11/23/2014 10:57:00 pl Before
2012146914 11/23/2014 11:04:00 claim Before
2012146914 12/1/2014 18:19:00 ca
2012181514 7/20/2015 16:20:00 ca
2012181514 7/20/2015 16:24:00 pl After
2012183018 3/17/2015 11:01:00 pl Before
2012183018 3/17/2015 11:28:00 pl Before
2012183018 3/17/2015 11:37:00 pl Before
2012183018 4/8/2015 16:50:00 ca
2012183018 4/8/2015 16:52:00 pl After
2012201789 11/15/2014 1:30:00 claim Before
2012201789 11/15/2014 1:55:00 ca
2012201789 11/15/2014 0:30:00 claim After
2012204480 1/10/2015 16:47:00 ca
2012204480 1/10/2015 16:48:00 pl After
2012223263 1/17/2015 10:54:00 ca
2012223263 1/17/2015 10:58:00 pl After
2012223263 4/4/2015 11:58:00 pl After
2012223263 12/21/2014 11:28:00 pl After