Oracle busca la lista de palabras en cadena y recupera las existentes

Aquí está la solución que busqué:

WITH dwtables(dwtable) AS (
  SELECT 'DWA' FROM dual UNION ALL
  SELECT 'DWB' FROM dual UNION ALL
  SELECT 'DWC' FROM dual

)--> Tabelle mit einem Spalte (Liste)

SELECT title, 
    (SELECT LISTAGG (dwtable, ', ' ) WITHIN GROUP (ORDER BY dwtable)
     FROM dwtables
    WHERE REGEXP_LIKE (r.querytext, '(^|\s)'||dwtables.dwtable||'(\s|$)', 'i')) AS dwtables

 FROM Reports r;