SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Subquery (alias b) (children 1)
     SelectWithUnionQuery (children 1)
      ExpressionList (children 1)
       SelectQuery (children 1)
        ExpressionList (children 1)
         Function randConstant (children 1)
          ExpressionList
   ExpressionList (children 3)
    Function equals (children 1)
     ExpressionList (children 2)
      Identifier b
      Identifier b
    Function equals (children 1)
     ExpressionList (children 2)
      Identifier a
      Identifier b
    Identifier a=a
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       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 2)
           Identifier a
           Function equals (alias a=a) (children 1)
            ExpressionList (children 2)
             Identifier a
             Identifier a
