Retrive n number of elements from the collection using XQUERY

Question

<?xml version="1.0"?>
<ns0:PNR >
    <ns0:num>num_1</ns0:num>
    <ns0:num>num_2</ns0:num>
    <ns0:num>num_3</ns0:num>
    <ns0:num>num_4</ns0:num>
    <ns0:num>num_5</ns0:num>
    <ns0:num>num_6</ns0:num>
    <ns0:num>num_7 </ns0:num>
</ns0:PNR>
In the above XMl i need an xquery to get below response:
<ns1:PNRSet >
<ns1:set>
<ns0:num>num_1</ns0:num>
    <ns0:num>num_2</ns0:num>
</ns1:set>
<ns1:set>
<ns0:num>num_3</ns0:num>
    <ns0:num>num_4</ns0:num>
</ns1:set>
<ns1:set>
<ns0:num>num_5</ns0:num>
    <ns0:num>num_6</ns0:num>
</ns1:set>
<ns1:set>
<ns0:num>num_7</ns0:num>
</ns1:set>
</ns1:PNRSet>

Answer 1

Declare @x xml ='<?xml version="1.0"?>
<ns0:PNR xmlns:ns0="whatever">
<ns0:num>num_1</ns0:num>
<ns0:num>num_2</ns0:num>
<ns0:num>num_3</ns0:num>
<ns0:num>num_4</ns0:num>
<ns0:num>num_5</ns0:num>
<ns0:num>num_6</ns0:num>
<ns0:num>num_7 </ns0:num>
</ns0:PNR>';
with xmlnamespaces ('whatever' as ns0, 'the other' as ns1)
, num as (
select num from (values(0), (1),(2),(3), (4), (5), (6), (7),(8),(9),(10)) x(num)
), setFull as (
select num / 2 as setNum, num + 1 as num
from num n
), setNum as (
select distinct setNum
from setFull
where @x.exist('/ns0:PNR/ns0:num[position() = sql:column("num")]') = 1
select
(Select
x.val.query('.')
from setFull s
cross apply @x.nodes('/ns0:PNR/ns0:num[position() = sql:column("num")]') x(val)
where n.setNum = s.setNum
for xml path (''), type)
from setNum n
for xml path ('ns1:set'), root('ns1:PNRSet')
Russel Loski, MCT, MCSE Data Platform/Business Intelligence. Twitter: @sqlmovers; blog: www.sqlmovers.com