>Every weekend I'm going to post about a few new features in SQL 2012 (note, in the new post category, there are versions for SQL that go up to SQL 2008....this one is for 2012, but I don't believe there's an entry in the version pulldown)
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>This feature is called the Sequence Object. This is an excerpt from a CoDe article I wrote last year (http://code-magazine.com/articleprint.aspx?quickid=1203051&printmode=true)
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>Have you ever wanted a table-independent identity generator within a database? Other databases (e.g. Oracle) have had a sequence generator to produce a new integer identity on demand, without association to a specific table. Imagine a scenario where you could create an integer value for every row in every table, where the value is unique across tables - and without the complexity of a uniqueidentifier.
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>The new sequence generator object in SQL Server 2012 allows database administrators to have a table-independent "factory": one that produces an integer value that will be unique across every table/row in the database. This effectively creates the equivalent of a uniqueidentifer within a database.
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>

>CREATE SEQUENCE DemoSequence START WITH 1 INCREMENT BY 1;
>
>SELECT NEXT VALUE FOR DemoSequence      -- Gives us 1...if you execute again, it will give you 2....note, it's thread safe, you can try it from multiple windows/tasks
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>CREATE TABLE MyTest  (SequenceValue int, Name varchar(50))
>go
>
>
> insert into MyTest values  
>     (next value for DemoSequence, 'Kevin Goff')
>
>

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>If you want to know the current value in a sequence (in the "factory")...
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>

select current_value from sys.sequences where name = 'DemoSequence'

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>You can use a sequence object in a default value...and it can even be a bigint (in case you need values beyond 2 billion)
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>

>CREATE SEQUENCE BigDemoSequence  START WITH 3000000000 INCREMENT BY 1000000
>go
>
>create table MyTestBigInt (sequenceint bigint   default next value for BigDemoSequence, Name varchar(50))
> 
>
>insert into MyTestBigInt  (Name) values  (  'test1')
>insert into MyTestBigInt (Name)  values  (  'test2')

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>
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>So...in SQL 2012, there usually won't be a need to use a uniqueidentifier, when you need to store unique int values across tables within a database. (Note: if you need to store unique values across rows across databases/database servers, this won't work....the scope of the uniqueness is within the database, which is still better than regular identity columns that are only unique within the table

Have I mentioned it's great to have you back? I think I have.