First record of a table by creation date with 2 more conditions

Question

I think this is easy to accomplish using OLAP functions, but I still haven't found the winning combination.

My table has the following fields:

• request_id
• corresp_id
• corresp_type
• corresp_status
• create_ts

For every request I have multiple correspondences of different kind and statuses.

I need to find the requests where the first correspondence, has corresp_type=3 and corresp_status=4

Answer 1

Find the first row for each request based on create_ts and check if it has corresp_type=3 and corresp_status=4

select request_id
from tab
qualify
   row_number() 
   over (partition by request_id
         order by create_ts) = 1 
and corresp_type=3 
and corresp_status=4