Indexed Views And Scalar UDFs

Question

Can UDFs be used inside index views or does this break the SCHEMABINDING logic?

For example if in the where clause of the view I had something like this

WHERE
     UserCanSeePost(UserId,PostId)

This UDF would then do a lookup on another table to check some restrictions. I'm guessing this cant be done in indexed views?

Answer 1

If the function is created WITH SCHEMABINDING, then you can use WITH SCHEMABINDING on a view built on top of it. I'm not 100% sure, but I think functions WITH SCHEMABINDING were introduced in SQL Server 2005...

Edit -> Nope, apparently you could use WITH SCHEMABINDING in 2000 as well.

Answer 2

Yes, if it's deterministic and itself has SCHEMABINDING

See Indexed views too:

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User-defined functions referenced in the view must have been created with the SCHEMABINDING option.
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All functions referenced by expressions in the view must be deterministic. The IsDeterministic property of the OBJECTPROPERTY function reports whether a user-defined function is deterministic. For more information, see Deterministic and Nondeterministic Functions.
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