sql - How to get the first and last dates/records from the employee history table -


lets emp hired on 10 apr 15 , transferred on 30 apr 15 , again promoted on 10 june 15. history need first , last (recent record) emp_data. action_date dates mentioned above. need 10 apr , 10 june output query. action refereed hire, transfer, etc.

this attempting-

select empid, action, action_dt ps_job action_dt in (select min(action_dt), max(action_dt) ps_job empid='88888');

but instead showing me 3 dates record.

i think have modify query following:

select empid, action, action_dt  ps_job  action_dt in (select min(action_dt)                      ps_job                      empid='88888'                      union                      select max(action_dt)                     ps_job                      empid='88888')

min , max should selected two separate rows, in clause works. 1 way use of union in above query.

demo here

alternatively can use row_number:

select empid, action, action_dt ( select empid, action, action_dt,        row_number() on (partition empid order action_dt) frn,        row_number() on (partition empid order action_dt desc) lrn ps_job ) t frn = 1 or lrn = 1

note version not equivalent first query, there may more 1 records having same max or min date. have replace row_number rank if want all max, min records selected.

demo here


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