本質的に、自動インクリメントはインクリメントの量だけ挿入ごとに進みます。
MS SQL Server は、逆順を作成する方法を提供します。こちらをご覧ください
create table #test
(
TestId INT IDENTITY (2, -1),
DateTimeStamp DateTime
)
GO
INSERT INTO #test (DateTimeStamp) Values (GETDATE());
INSERT INTO #test (DateTimeStamp) Values (GETDATE());
INSERT INTO #test (DateTimeStamp) Values (GETDATE());
INSERT INTO #test (DateTimeStamp) Values (GETDATE());
INSERT INTO #test (DateTimeStamp) Values (GETDATE());
INSERT INTO #test (DateTimeStamp) Values (GETDATE());
INSERT INTO #test (DateTimeStamp) Values (GETDATE());
INSERT INTO #test (DateTimeStamp) Values (GETDATE());
GO
SELECT * FROM #test
結果:
TestId DateTimeStamp
2 2009-07-28 15:02:09.200
1 2009-07-28 15:02:09.200
0 2009-07-28 15:02:09.200
-1 2009-07-28 15:02:09.200
-2 2009-07-28 15:02:09.203
-3 2009-07-28 15:02:09.203
-4 2009-07-28 15:02:09.203
-5 2009-07-28 15:02:09.207