>>Hi Mike,
>>
>>>WOW! OK, that's cool, but you didn't make the join expressions exactly match the index expressions. Made me wonder if there's any harm in doing so. It works fine.
>>>
>>
>>As far as I know it is not necessary to modify WHERE clause because UDF arguments in a WHERE are always passed by value.
>
>It may not be necessary, but if there is a simple rule like where clause should exactly match index expression it's easier to build apps. Remembering the intricate details of what is necessary in this case versus that case is the definition of steep learning curve.

Sure it is (a steeper learning curve). But the converse is that restricting the rules set to one is "dumbing down", which in my opinion is much worse. Of course it follows that the rules MUST be written in the product documentation, in sensible places, well cross-referenced. Decidedly not like, say, the "EXISTS" clause of Select-SQL < s >.

cheers



>
>>
>>>Doesn't that exclude passing an array by reference to the UDF?
>>>
>>
>>Yes, but that's the behavior that WHERE has, parameters are not passed by ref (see my answer above). So, if key expression passes parameter by ref, it doesn't match an expression in WHERE.
>>
>>Thanks,
>>Aleksey.