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Four Rules for NULLs

In SQL Server 2000 or any relational database, the concept of NULL can be both confusing and hazardess to your employment. Not understanding how to work with NULLs can lead to incorrect responses to queries and poor business decisions being made. New author Michael Coles brings us four rules that can help you work with NULL values in your tables.

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2008-03-28 (first published: )

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Question of the Day

Checking Identities

The DBCC CHECKIDENT command is used when working with identity values. I have a table with 10 rows in it that looks like this:

TravelLogID CityID  StartDate   EndDate
1           1       2025-01-11  2025-01-16
2           2       2025-01-11  2025-01-16
3           3       2025-01-11  2025-01-16
4           4       2025-01-11  2025-01-16
5           5       2025-01-11  2025-01-16
6           6       2025-01-11  2025-01-16
7           7       2025-01-11  2025-01-16
8           8       2025-01-11  2025-01-16
9           9       2025-01-11  2025-01-16
10          10      2025-01-11  2025-01-16
The docs for DBCC CHECKIDENT say this if I run with only the table parameter: "If the current identity value for a table is less than the maximum identity value stored in the identity column, it is reset using the maximum value in the identity column. " I run this code:
DELETE dbo.TravelLog WHERE TravelLogID >= 9
GO
DBCC CHECKIDENT(TravelLog, RESEED)
GO
INSERT dbo.TravelLog
(
    CityID,
    StartDate,
    EndDate
)
VALUES
(4, '2025-09-14', '2025-09-17')
GO
What is the identity value for the new row inserted by the insert statement above?

See possible answers