CREATE TABLE duplicate_records_2 AS
SELECT ROWNUM rn, A.* FROM duplicate_records_1 A
;
SELECT A.*
FROM duplicate_records_2 A,
(
SELECT account_no, MIN(ROWNUM) min_row_num
FROM duplicate_records_1
GROUP BY account_no
) b
WHERE A.account_no = b.account_no
AND A.rn = b.min_row_num
;
我會咁寫
SELECT *
FROM
(
SELECT
a.*
, ROW_NUMBER() OVER (PARTITION BY ACCOUNT_NO ORDER BY INPUT_DATE ASC) AS ROW_NUM
FROM a
)
WHERE ROW_NUM = 1
[fix comma @ 2016 March 31 22:38]