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Null Semantics (LINQ to SQL)

The following table provides links to various parts of the LINQ to SQL documentation where null (Nothing in Visual Basic) issues are discussed.

Topic

Description 

SQL-CLR Type Mismatches (LINQ to SQL)

The "Null Semantics" section of this topic includes discussion of the three-state SQL Boolean versus the two-state common language runtime (CLR) Boolean, the literal Nothing (Visual Basic) and null (C#), and other similar issues.

Standard Query Operator Translation (LINQ to SQL)

The "Null Semantics" section of this topic describes null comparison semantics in LINQ to SQL.

System.String Methods (LINQ to SQL)

The "Differences from .NET" section of this topic describes how a return of 0 from LastIndexOf might mean either that the string is null or that the found position is 0.

How to: Compute the Sum of Values in a Numeric Sequence (LINQ to SQL)

Describes how the Sum operator evaluates to null (Nothing in Visual Basic) instead of 0 for a sequence that contains only nulls or for an empty sequence.

See Also

Other Resources

Data Types and Functions (LINQ to SQL)