Empty Record giving display Errors

Question

Hi All, 
 I have a page in my site pointing to a record. When I don't specify any default filters, I am able to fetch all the rows from the database table and display in the record. But when I am giving a filter on the user who inserted the record into the table, it is giving me error. 
 When the query "user_txt" is null, I am getting the error 
 "The Requested Record Type is Not Available: Cannot apply operator [EQUALS] to field [user_txt] when comparing to value [TypedValue[it=11, v={abanda}]].{APNX-1-4203-015}" 
 I was not able to find a solution in the forum except removing the UI on a whole with a showonly condition in case of a null set. 
 Please assist if anyone has worked on a fix on this. 
 
 Thanks, 
 Adi

Josh · Accepted Answer

I would suggest modifying your rule to return a single text field. Your filter is using the equals operator but your rule returns a list (Appian type 103) and you get the error shown above.

Meg Guckenberg · Answer

Your rule getUserGroup(loggedInUser()) is returning a List of Text String, which is type 103 as you see in the error. You cannot use the "=" operator for a list of values, which is why you're receiving the error. To fix this, make sure that rule will only ever return a single value and that the response is of the same type as "audience_txt". Also, depending on the format of that rule, it may be returning an empty array ({}) which is being treated like a list of text string even though it looks null.