för att få en beställd lista finns det några sätt. det enklaste är:
select id, str
from (select id,
wm_concat('level : ' || to_char(nvl(eventDate,SYSDATE - 365 * 100)))
over (partition by id order by eventdate) str,
row_number() over (partition by id order by eventdate desc) rn
from Mytable)
where rn = 1;
eller om du använder det "stragg" användardefinierade aggregatet:
select id, str
from (select id,
string_agg('level : ' || to_char(nvl(eventDate,SYSDATE - 365 * 100)))
over (partition by id order by eventdate) str,
row_number() over (partition by id order by eventdate desc) rn
from Mytable)
where rn = 1;
t.ex.
SQL> select id, str
2 from (select id,
3 string_agg('level : ' || to_char(nvl(eventDate,SYSDATE - 365 * 100)))
4 over (partition by id order by eventdate) str,
5 row_number() over (partition by id order by eventdate desc) rn
6 from Mytable)
7 where rn = 1;
ID STR
---------- ----------------------------------------------------------------------
1 level : 27-MAR-08,level : 27-JAN-09,level : 02-APR-10
2 level : 07-JUN-06,level : 02-NOV-08,level : 27-DEC-08
3 level : 27-MAR-06,level : 02-APR-10,level : 27-JUL-10