Hi michael,

I just tested with a column which can be null, and it works great. I suppose you want to return the items where DocumentType is null.

1. Do you have a DocumentType which value is empty/null?
2. Do you have an error thrown?
3. Did you try to use the Lookup ID instead of the Lookup value (and specify LookupId="true" in the FieldRef node)?

I'm looking forward to hearing from you,

Regards,
Marien Monnier
Enesys

Hi michael,

Just to be sure that you can use the Lookup ID, can you have several DocumentType with the same value but not the same ID?

If not, in order to use the Lookup ID, while keeping the Lookup value displayed, you would do something similar to :

1. Update your dataset which returns the distinct DocumentType from the Documents list to retrieve the ID and the Title instead of just retrieving the Title
2. Update your parameter properties to something similar to:
   
   The users would still see the Document Types, but the parameter values would be the Lookup IDs
3. Update your second dataset query and add LookupId="true" in the FieldRef element:
   <Eq>
     <FieldRef Name="DocumentType" LookupId="true" />
     <Value Type="Lookup">@rptDocumentType!</Value>
     <IfNot>All</IfNot>
   </Eq>

But, if you can have several DocumentTypes with the same value and not the same ID, I would appreciate some more data so I can reproduce this issue. If you could send us your lists to our support address (available in the last page of the documentation), I would be able to further help you.

Regards,
Marien Monnier
Enesys

Hi michael,

Indeed, I thought you had a DocumentType which value is null in your document types. It would still have an ID in this case, so my answer does not apply for your case.

I was able to do something using an sqlQuery statement, but you will loose a little bit on performances.

Remove your Eq filter from your Caml Query and add an sqlQuery similar to this one:

<sqlQuery tableName="res">
SELECT * FROM Documents
WHERE (DocumentType = @param! OR @param! = "All")
OR (@param! IS NULL AND DocumentType IS NULL)
</sqlQuery>

The first condition is to do the IfNot behavior, and the second one is to take care of the Null DocumentType.

I hope this help this time.

Regards,
Marien Monnier
Enesys