XML to SQL - SQL Server - sql

Question

I'm traversing an XML file to read nodes and fill into to SQL Server tables. I have a Root node having Department node which further may have one or more as element. I want to select all the possible values from in a SQL result set.
Please find below XML I'm referring:
DECLARE #x XML='
<Root>
<Department>
<DeptID>D101</DeptID>
<DeptID>D102</DeptID>
</Department>
</Root>'
I'm using below SQL Query to get the data from XML but I can read only first DeptID as I'm passing [1] inside DeptID[1]. If I pass [2] I can get thee second value. But in real life scenario, I won't be able to know how many DeptID would be there in the XML. So I want a generic script to read as many as DeptIDs comes in XML.
SELECT n.value('DeptID[1]','varchar(10)') AS DeptID FROM #x.nodes('/Root/Department') R(n)

Answer 1

You can use OpenXMl method of sql server to get more elements in table as follows.
Step 1: Suppose this is your sample XML data.
DECLARE #XML XML='
<ROOT>
<Customers>
<Customer CustomerID="C001" CustomerName="Arshad Ali">
<Orders>
<Order OrderID="10248" OrderDate="2012-07-04T00:00:00">
<OrderDetail ProductID="10" Quantity="5" />
<OrderDetail ProductID="11" Quantity="12" />
<OrderDetail ProductID="42" Quantity="10" />
</Order>
</Orders>
<Address> Address line 1, 2, 3</Address>
</Customer>
<Customer CustomerID="C002" CustomerName="Paul Henriot">
<Orders>
<Order OrderID="10245" OrderDate="2011-07-04T00:00:00">
<OrderDetail ProductID="11" Quantity="12" />
<OrderDetail ProductID="42" Quantity="10" />
</Order>
</Orders>
<Address> Address line 5, 6, 7</Address>
</Customer>
<Customer CustomerID="C003" CustomerName="Carlos Gonzlez">
<Orders>
<Order OrderID="10283" OrderDate="2012-08-16T00:00:00">
<OrderDetail ProductID="72" Quantity="3" />
</Order>
</Orders>
<Address> Address line 1, 4, 5</Address>
</Customer>
</Customers>
</ROOT>'
Step 2: Use of OPENXML method to get elements at any level as follows.
DECLARE #hDoc AS INT, #SQL NVARCHAR (MAX)
EXEC sp_xml_preparedocument #hDoc OUTPUT, #XML
SELECT CustomerID, CustomerName, Address, OrderID, OrderDate, ProductID, Quantity
FROM OPENXML(#hDoc, 'ROOT/Customers/Customer/Orders/Order/OrderDetail')
WITH
(
CustomerID [varchar](50) '../../../#CustomerID',
CustomerName [varchar](100) '../../../#CustomerName',
Address [varchar](100) '../../../Address',
OrderID [varchar](1000) '../#OrderID',
OrderDate datetime '../#OrderDate',
ProductID [varchar](50) '#ProductID',
Quantity int '#Quantity'
)
EXEC sp_xml_removedocument #hDoc
GO
Above steps will give you following Output.

Answer 2

Try it like this
DECLARE #x XML='
<Root>
<Department>
<DeptID>D101</DeptID>
<DeptID>D102</DeptID>
</Department>
</Root>';
SELECT d.value('text()[1]','varchar(10)') AS DeptID
FROM #x.nodes('/Root/Department/DeptID') A(d);
Your own code
SELECT n.value('DeptID[1]','varchar(10)') AS DeptID
FROM #x.nodes('/Root/Department') R(n)
... follows the right idea. But .nodes() must return the repeating element, which is <DeptID>. Your approach is looking for the first <DeptID> within <Department> actually