If you have a multiselect parameter but you would like to have the “None” option added to it here is how you can accomplish it. The None option assumes that you would like to display entities (records) that might not have values:
We will assume that ID is of type uniqueidentifier.
‘00000000-0000-0000-0000-000000000000’ AS ID
, ‘_None’ as Name
Main Dataset Query:
WHERE ISNULL(ID, ‘00000000-0000-0000-0000-000000000000’) IN (@yourParameter)