Suggest answer

[gvraghuramraju]

Please suggest correct answer (A,B,C,D) for the following Question

You are developing an application for a worldwide furniture wholesaler. You need to create an inventory table on each of the databases located in New York, Chicago, Paris, London, San Francisco, and Tokyo. In order to accommodate a distributed environment, you must ensure that each row entered into the inventory table is unique across all location. How can you create the inventory table?

A. Use the identity function. At first location use IDENTITY(1,4), at second location use IDENTITY(2,4), and so on.
B. Use the identity function. At first location use IDENTITY(1,1), at second location use IDENTITY(100000,1), and so on.
C. CREATE TABLE inventory ( Id Uniqueidentifier NOT NULL DEFAULT NEWID(), ItemName Varchar(100) NOT NULL, ItemDescription Varchar(255) NULL, Quantity Int NOT NULL, EntryDate Datetime NOT NULL).
D. Use TIMESTAMP data type.

[skhanal]

I would choose C

[ravinder_k]

I would like you to see the flip side of choice 'c'. This is extracted form BOL

The main advantage of the uniqueidentifier data type is that the values generated by the Transact-SQL NEWID function or the application GUID functions are guaranteed to be unique throughout the world.

The uniqueidentifier data type has several disadvantages:

The values are long and obscure. This makes them difficult for users to type correctly, and more difficult for users to remember.
The values are random and cannot accept any patterns that may make them more meaningful to users.
There is no way to determine the sequence in which uniqueidentifier values were generated. They are not suited for existing applications that depend on incrementing key values serially.
At 16 bytes, the uniqueidentifier data type is relatively large compared to other data types such as 4-byte integers. This means indexes built using uniqueidentifier keys may be relatively slower than implementing the indexes using an int key.

[gvraghuramraju]

ThanQ guys for ur reply with neat description