How to retrieve all child elements for all parent elements from xml in sql

Question

<people>
<parent>
  <parent-name> joel </parent-name>
  <child> john </child>
  <child> sara </child>
  <child> ram </child>
</parent>

<parent>
  <parent-name> sam </parent-name>
  <child> david </child>
  <child> george </child>
  <child> wilson </child>
</parent>
</people>

the desired output is:

parent  |  child
--------|---------
joel    |  john
joel    |  sara
joel    |  ram
sam     |  david
sam     |  george
sam     |  wilson

I tried the following sql query to retrieve all child element for all parent, only I can get first child element

select a.b.value('parent-name[1]','varchar(50)') as parent
      , a.b.value('child[1]' ,'varchar(50)') as child
from @myxml.nodes('people/parent')a(b)

Answer 1

You need to use CROSS APPLY and .nodes() on the <child> nodes of each parent node:

SELECT
    a.b.value('(parent-name)[1]', 'varchar(50)') as parent, 
    XChild.value('.' ,'varchar(50)') as child
FROM
    @myxml.nodes('people/parent') AS a(b)
CROSS APPLY
    b.nodes('child') AS XTbl(XChild)    

This will return all parents with all their children.

Answer 2

The trick is to iterate the children, then go up one level and get the parent name.

select a.b.value('(../parent-name)[1]','varchar(50)') as parent
  , a.b.value('(.)[1]' ,'varchar(50)') as child
from @myxml.nodes('people/parent/child')a(b)