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I use SQL Server 2008 and Entity framework 4.1 database first approach .

Is there any way I could create null-able Computed column ?

I can't create like this : 

Alter Table Employee Add FullName nullable as LastName + ' ' +FirstName

If the answer is NO , then Is there any way I could make the appropriate Scalar Property Nullable in EDMX File of EF Which map to Computed column ?

Mostafa
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1 Answers1

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Computed columns by default nullable is the expression involves any other nullable column, expression or any function. If you want NON-NULL computed column, you should wrap the column's expression with ISNULL function.

Alter Table Employee Add FullName as LastName + ' ' +FirstName

In this case FullName will be nullable only if one of columns (FirstName, LastName) will be nullable too

If you want nullable computed column composed witn non-nullable expression columns, then use the User Defined function as expression:

CREATE FUNCTION dbo.FullName(@LastName nvarchar(100), @FirstName nvarchar(100))
RETURNS nvarchar(201)
AS
BEGIN
  RETURN @LastName + N' ' +@FirstName
END
GO

Alter Table Employee Add FullName as dbo.FullName(LastName, FirstName)
Oleg Dok
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