How can I declare a temporary table in the Jazz Reporting Service?

Hello

I'm trying to create a report in the Jazz Reporting Service (JRS). I want the report display counts of different data in different columns, in order to accomplish this I need to do a lot of joins. Because I want my query to be readable and maintainable I wanted to save a temporary table which I can join on several times. But I can't quite figure out the appropriate syntax.

I've tried a number of different variants:

DECLARE @result1 TABLE (Feature_ID INT, Story_Name VARCHAR)

INSERT INTO @result1
	SELECT T1.REFERENCE_ID AS Feature_ID, T1.NAME AS Story_Name
	FROM RIDW.VW_REQUEST T1

SELECT DISTINCT
	Epics.REFERENCE_ID AS Epic_ID,
	...
	
	
	

Resulting in the Error:
CRRGW5628E An com.foundationdb.sql.parser.SQLParserException error occurred when validating the input SQL string, caused by Lexical error at line 1, column 9. Encountered: "@" (64), after : "".

DECLARE TABLE result1
     (Feature_ID	INTEGER,
      Feature_Name	VARCHAR);
      
INSERT INTO result1
	SELECT T1.REFERENCE_ID AS Feature_ID, T1.NAME AS Story_Name
	FROM RIDW.VW_REQUEST T1

SELECT DISTINCT 
	Epics.REFERENCE_ID AS Epic_ID,
        ...
	
	

This does instead result in this error:

I've tried adding and removing @-signs and combining variants of these. But nothing seems to work.
Does anyone know the correct syntax for doing this?