Remove xml node based on value

Question

Hi,
we have to remove elements bases on the value.
for example consider below xml
<htl:room>
          <htl:ratePlan>
            <htl:freeNights>12</htl:freeNights>
            <htl:promoSavings>undefined</htl:promoSavings>
            <htl:tax>undefined</htl:tax>
          </htl:ratePlan>
          <htl:guestAllocation>1,2</htl:guestAllocation>
        </htl:room>
We have to remove elements with value undefined and should construct a new xml as below
<htl:room>
          <htl:ratePlan>
            <htl:freeNights>12</htl:freeNights>
          </htl:ratePlan>
          <htl:guestAllocation>1,2</htl:guestAllocation>
        </htl:room>
please help.
Thanks

Answer 1

i assume that loc always corresponds to name. So to find the rows to remain is just a simple group by
with data as(
select 'aaa' name,'a1' loc,10 count from dual union all
select 'aaa','a1',0 from dual union all
select 'bbb','b1',0 from dual union all
select 'ccc','c1',0 from dual union all
select 'dcc','d1',11 from dual union all
select 'dcc','d1',0 from dual )
select
  name
, loc
, max(count) cnt
from data
group by
  name
, loc
order by
  name
, loc
NAME     LOC     CNT
aaa     a1     10
bbb     b1     0
ccc     c1     0
dcc     d1     11to find the other is just a minus
with data as(
select 'aaa' name,'a1' loc,10 count from dual union all
select 'aaa','a1',0 from dual union all
select 'bbb','b1',0 from dual union all
select 'ccc','c1',0 from dual union all
select 'dcc','d1',11 from dual union all
select 'dcc','d1',0 from dual )
select name,loc,count from data
minus
select
  name
, loc
, max(count) cnt
from data
group by
  name
, loc
order by
  name
, loc
NAME     LOC     COUNT
aaa     a1     0
dcc     d1     0so a delete would be
delete from data
where
(name,loc,count)
in
(select name,loc,count from data
minus ..regards