行号和分区

Question

My data looks like this -

CALENDAR    CLIENTID
20180801    178
20180802    178
20180803    578

The max(calendar) for clientid 178 is 20180802 . How do I get the row_number for max(calendar) per clientid . In the case of client 178 , it would be 2 because it is the second row. This is what I have so far -

 select clientid, 
 ROW_NUMBER() OVER ( partition by clientid ORDER BY max(calendar) desc )
 from STATS
 group by clientid

Answer 1

You can just count the rows for each client:

select clientid, count(*)
from stats
group by clientid;

This is the maximum of the "row number".