SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Subquery (alias a) (children 1)
     SelectWithUnionQuery (children 1)
      ExpressionList (children 1)
       SelectQuery (children 1)
        ExpressionList (children 1)
         Function randConstant (children 1)
          ExpressionList
   ExpressionList (children 1)
    Function equals (children 1)
     ExpressionList (children 2)
      Identifier a
      Identifier a
