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Can this table have a FK?

Posted on 2011-09-08
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Last Modified: 2012-05-12
In SQL Server 2005, I've added a new table: TableNew.  In an existing table, I've added a new column that is a reference to TableNew:

    OldTable.TableNewId

TableNewId will have to allow null since there are records in the table.  New records will add a value in this column. Since the column allows null, is it possible to create a FK to TableNew.TableNewId?  Is that needed at this point?
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Question by:brettr
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Ephraim Wangoya earned 2000 total points
ID: 36506983

You can create the key but you cant have any referential integrity checks
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by:brettr
ID: 36507021
What good is the key in that case?
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by:Ephraim Wangoya
ID: 36507216
Precisely
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