?

SQL> select * from aaa;

??????? ID???? SEQ_ID NAME
---------- ---------- --------------------
???????? 1????????? 1 A
???????? 1????????? 2 A
???????? 1????????? 3 A
???????? 2????????? 1 B
???????? 2????????? 2 B
???????? 3????????? 1 C
???????? 3????????? 2 C
???????? 3????????? 3 C
???????? 3????????? 4 C

9 rows selected

SQL>?
SQL>? SELECT *
? 2??? FROM AAA A
? 3?? WHERE A.SEQ_ID = (SELECT MAX(B.SEQ_ID) FROM AAA B WHERE B.ID = A.ID)
? 4? /

??????? ID???? SEQ_ID NAME
---------- ---------- --------------------
???????? 1????????? 3 A
???????? 2????????? 2 B
???????? 3????????? 4 C

www.cnoug.org?论坛 yesl

SQL> SELECT ID, SEQ_ID, NAME
? 2??? FROM (SELECT ID,
? 3???????????????? SEQ_ID,
? 4???????????????? NAME,
? 5???????????????? RANK() OVER(PARTITION BY ID ORDER BY SEQ_ID DESC NULLS LAST) DRN
? 6??????????? FROM AAA)
? 7?? WHERE DRN =1
? 8? /

??????? ID???? SEQ_ID NAME
---------- ---------- --------------------
???????? 1????????? 3 A
???????? 2????????? 2 B
???????? 3????????? 4 C