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CREATE TABLE #HIST
(
ACCT_ID INT,
ACCT_SEQ INT,
HISTORY_SEQ INT,
ACCT_STATUS CHAR(1),
ASSIGNED_DATE DATETIME,
EXPIRED_DATE DATETIME,
ID VARCHAR(50)
)
INSERT INTO #HIST VALUES
(101, 1, 1,'A','1/12/2015 15:40','1/13/2015 8:00','NO_ID'),
(101, 1, 2,'A','1/13/2015 8:00','3/3/2017 19:43','9596025'),
(101, 1, 3,'A','3/3/2017 19:43',NULL,'9596025'),
(102, 1, 4,'A','1/18/2015 15:40','1/13/2015 8:00','NO_ID'),
(102, 1, 5,'A','1/15/2015 8:00','3/3/2017 19:43','9596025'),
(102, 1, 6,'A','3/3/2017 19:43',NULL,'9596025')
SELECT *
,ROW_NUMBER()OVER(Partition by ACCT_ID order by HISTORY_SEQ asc) as RID
INTO #ResultID
FROM #HIST
UPDATE H
SET H.ASSIGNED_DATE=R.ASSIGNED_DATE
FROM #ResultID R
INNER JOIN #ResultID R1 ON R.ACCT_ID=R1.ACCT_ID and R.RID= R1.RID-1
INNER JOIN #HIST H ON H.ACCT_ID=R1.ACCT_ID AND H.HISTORY_SEQ=R1.HISTORY_SEQ
WHERE R.ID='NO_ID'
select * from #HIST where ID<>'NO_ID'
drop table #HIST
drop table #ResultID