A better way to generate the needed XML?

Question

I am working on a 10.2 system and looking to see if there is a better way to generate the resulting XML than what I have come up with. Here is a test case and the output it generates. I don't really like querying the table for each column needed as the real table has eight columns I am pulling. I would like to make one pass on person_h and get the info needed instead of making eight passes, but not sure if it is possible.
with person_h as
   (select 1 id, 'M' gender, 'W' race, '170' weight from dual union all
    select 1, 'M', 'W', '170' from dual union all
    select 1, 'M', 'W', '180' from dual union all
    select 1, 'M', NULL, '175' from dual union all
    select 1, NULL, 'W', NULL from dual
select xmlelement("Person",
         (select xmlagg(xmlelement("Sex", gender))
            from (select distinct gender
                    from person_h
                   where id = 1
                     and gender is not null) pg),
         (select xmlagg(xmlforest(race as "Race"))
            from (select distinct race
                    from person_h
                   where id = 1) pg),
         (select xmlagg(xmlforest(weight as "Weight"))
            from (select distinct weight
                    from person_h
                   where id = 1) pg)
       ).getstringval()
  from dual;
Output
<Person>
  <Sex>M</Sex>
  <Race>W</Race>
  <Weight>170</Weight>
  <Weight>175</Weight>
  <Weight>180</Weight>
</Person>Note: Previously posted on the XML DB forum at A better way to generate the needed XML? but still looking for other solutions so putting in front of more eyes here. I have considered using a WITH statement to do the initial query on person_h but haven't tested that yet to see what Oracle really will do as just getting back around to this lower priority task of mine.

Answer 1

I'm using the WITH statement to simulate a table and DUAL/UNION ALL to create data in that "table". I've seen it used plenty of times in this forum so not sure why a problem for this example. The actual SQL/XML statement hits that "base table" three times, so I didn't include all eight columns because three columns is sufficient to show the problem in the way I coded the SQL. Following the SQL is the sample OUTPUT that SQL statement generates and that is the output I created and need. I'm just looking for other options to achieve the listed output.