ORA-00932 on subquery join from subquery join
LOB Rules and Restrictions


  ...
  
  
  You cannot specify LOB columns in the ORDER BY clause of a query, the
  GROUP BY clause of a query, or an aggregate function.
  You cannot specify a LOB column in a SELECT... DISTINCT or SELECT...
  UNIQUE statement or in a join. However, you can specify a LOB
  attribute of an object type column in a SELECT... DISTINCT statement,
  a query that uses the UNION, or a MINUS set operator if the object
  type of the column has a MAP or ORDER function defined on it.
  
  
  ...