Question

I’m using sql server 2005

the idea is to create a column, update the values to 0, make it not nullable then, and recreate an existing PK adding it to the list
so far i’ve got this :

IF NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'MyTable' AND COLUMN_NAME = 'Division')
BEGIN
   ALTER TABLE MyTable ADD Division int NULL
   UPDATE MyTable SET Division = 0
   ALTER TABLE MyTable ALTER COLUMN Division int NOT NULL

   ALTER TABLE [dbo].[MyTable] DROP CONSTRAINT [PK_MyTable]

    ALTER TABLE [dbo].[MyTable] ADD  CONSTRAINT [PK_MyTable] PRIMARY KEY CLUSTERED 
    (
        [ID] ASC,
        [OfferCode] ASC,
        [StationCode] ASC,
        [Market] ASC,
        [Division] ASC
    )WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]   

END

The problem is that i need a “GO” statement so that the new column is created, otherwise i get an error when trying to update the values to 0. If i put a “GO” statement, then the if clause doesn’t work (because the column now exists). i was thinking of putting that status to a variable like @ColumnWasCreated, but the “GO” statement is like starting a whole new script, and the variable’s value is lost
any ideas??

Answer 1

OPTION 1

Instead of GO, try a TRANSACTION that encompasses the ADD COLUMN; then commit it and see if you can UPDATE.

OPTION 2

Try setting a default value constraint when you ADD COLUMN, this way, you won’t have to UPDATE or ALTER to not allow nulls.