sql - Nesting qualify statements in Teradata -


is possible "nest" qualify statements in teradata?

i have data looks this:

event_id = 1:   user_id        action_timestamp  971,134,265   17mar2010 20:16:56  739,071,748   17mar2010 22:19:59  919,853,934   18mar2010 15:47:49  919,853,934   18mar2010 15:55:21  919,853,934   18mar2010 16:01:20  919,853,934   18mar2010 16:01:48  919,853,934   18mar2010 16:04:52  472,665,603   20mar2010 18:23:58  472,665,603   20mar2010 18:24:07  472,665,603   20mar2010 18:24:26   ....  event_id = 2:       971,134,265   17mar2069 20:16:56  739,071,748   17mar2069 22:19:59  919,853,934   18mar2069 15:47:49  919,853,934   18mar2069 15:55:21  919,853,934   18mar2069 16:01:20  919,853,934   18mar2069 16:01:48  919,853,934   18mar2069 16:04:52  472,665,603   20mar2069 18:23:58  472,665,603   20mar2069 18:24:07  472,665,603   20mar2069 18:24:26 

for user 919,853,934, grab "18mar2010 16:04:52" action (the last 1 in first cluster of events).

i tried this, not grab right date:

select action_timestamp        ,user_id        ,event_id table ... qualify (     max(action_timestampt) on (partition user_id, event_id) = action_timestamp     , min(action_timestamp) on (partition user_id) = action_timestamp )  

this makes sense since max , min apply whole data, rather sequentially.

i tried 2 separate qualify statements min() part apply subset of data created max() part, errors.

this seems accomplish want:

select * (select *   table   ...   qualify (max(action_date) on (partition user_id, event_id) = action_date) ) qualify (     min(a.action_date) on (partition a.user_id) = a.action_date ) 

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