SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Asterisk
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier l
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier r
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier l.luid
        Identifier r.ruid
   Function and (children 1)
    ExpressionList (children 2)
     Function isNull (children 1)
      ExpressionList (children 1)
       Identifier luid
     Function isNotNull (children 1)
      ExpressionList (children 1)
       Identifier ruid
