SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 3)
    Identifier a
    Identifier b
    Function cume_dist (children 1)
     ExpressionList
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier test_cume_dist
   ExpressionList (children 2)
    OrderByElement (children 1)
     Identifier b
    OrderByElement (children 1)
     Identifier a
