>>>>>Hi,
>>>>>
>>>>>What would be the TSQL syntax to check if a column is set to be an Indenity column (Is Identity = Yes)? And if No, how to do set the column in Identity Yes in code?
>>>>>
>>>>>TIA
>>>>
>>>>Sys.columns has IsIdentity bit column, e.g.
>>>>
>>>>if exists (SELECT name, is_identity
>>>>FROM sys.columns
>>>>WHERE [object_id] = object_id('items')
>>>>and is_identity = 1)
>>>>
>>>>print 'Table Items has identity column'
>>>>
>>>>(If you know the column name, just check it using a similar script).
>>>>
>>>>If you want to make the column to be identity, you need to re-create the table (e.g. if you don't want to preserve current values, you can do
>>>>

>>>>select identity (int,1,1) as NewIdentityColumn, col1, col2, ... 
>>>>into myNewTable
>>>>from myTable

>>>
>>>The code (above that checks if a table has identity) works. How do I change it if I want to include the column name. That is, if I want to know if a certain column in table 'items' is identity?
>>>
>>>On the last point, I do want to preserve the current value in the column before making it an identity. From this point, the column value will be incremented then. So I do not want to recreate the table.
>>>
>>>Thank you for your help.
>>>
>>>UPDATE. I know that on my first question I just need to specify the name of the column in the WHERE. Got it.
>>
>>For the first question, it.is
>>
>>select * from sys.columns where name = 'myColumnName' and object_id = object_id('MyTable')
>>
>>You still need to re-create the table, so
>>

>>create myNewTable (.....) -- same structure as original, but with identity attribute for the right column
>>
>>set identity_insert  dbo.MyNewTable ON
>>
>>insert into myNewTable (Col1, Col2, Col3)
>>select Col1, Col2, Col3 from myOriginalTable
>>
>>set identity_insert  dbo.MyNewTable OFF
>>
>>drop table myOriginalTable
>>execute sp_rename 'MyOriginalTable', 'MyNewTable'
>>

>
>Thank you for the code. I will, however, change it in SSMS. The table could have like 500,000 records and many columns. So copying from the existing into a temp could be long or a problem. I suppose SSMS does it faster.

If you read Pinal's article, you'll find out that SSMS uses exactly the same script behind the scenes. So, it's not faster.