Extracting data from XML using OpenXML in SQL Server

Question

I have a xml which I want it to be extracted using OpenXML within SQL Server

Here is the sample XML

<row>
  <student_token>7</student_token>
  <student_ssn>552</student_ssn>
  <alternate_id>20</alternate_id>
  <old_ssn xsi:nil="true" />
  <alien_num xsi:nil="true" />
  <last_name>A</last_name>
  <first_name>B</first_name>
  <middle_init xsi:nil="true" />
  <drivers_license_num xsi:nil="true" />
  <gpa_highschool xsi:nil="true" />
  <created_dt>2006-07-13T11:15:08.320</created_dt>
  <created_how>4</created_how>
  <modified_dt>2008-02-14T00:00:00</modified_dt>
  <modified_by>4</modified_by>
  <primary_street2 xsi:nil="true" />
  <primary_street3 xsi:nil="true" />
  <primary_country xsi:nil="true" />
  <email_address xsi:nil="true" />
  <address_start_dt xsi:nil="true" />
  <address_end_dt xsi:nil="true" />
  <entrance_iv_dt xsi:nil="true" />
  <entrance_iv_by xsi:nil="true" />
  <exit_iv_dt>2006-11-02T00:00:00</exit_iv_dt>
  <exit_iv_by>156</exit_iv_by>
  <foreign_address_indicator>N</foreign_address_indicator>
  <foreign_postal_code xsi:nil="true" />
  <pin>J27841</pin>
  <web_id>J08614   </web_id>
  <prior_name xsi:nil="true" />
  <orig_eps xsi:nil="true" />
  <web_role>STU1</web_role>
  <heal_limit_flag>N</heal_limit_flag>
  <email_address_2>[email protected]</email_address_2>
  <cellular_telephone>415</cellular_telephone>
  <alt_loan_debt xsi:nil="true" />
  <web_last_login xsi:nil="true" />
  <foreign_country_code xsi:nil="true" />
  <entrance_iv_dt_grad_plus xsi:nil="true" />
  <entrance_iv_by_grad_plus xsi:nil="true" />
  <failed_logins>0</failed_logins>
  <hispanic xsi:nil="true" />
  <race xsi:nil="true" />
  <primary_phone_number_intl xsi:nil="true" />
  <security_version>0</security_version>
  <failed_challenge_response>0</failed_challenge_response>
  <require_pin_reset xsi:nil="true" />
</row>

The query should extract into 3 fields for each row

1. FieldName
2. FieldValue
3. IsNull

For example the first row should be

• FieldName = student_token - The node name would be the field name
• FieldValue = 7
• IsNull = false - IsNull is based on the attribute xsi:nil="true"

How can I do this? Any help would be appreciated.

Thanks

Answer 1

Sample data with namespace added.

declare @xml xml 
set @xml = 
'<row xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <student_token>7</student_token>
  <student_ssn>552</student_ssn>
  <alternate_id>20</alternate_id>
  <old_ssn xsi:nil="true" />
  <alien_num xsi:nil="true" />
  <last_name>A</last_name>
  <first_name>B</first_name>
  <middle_init xsi:nil="true" />
  <drivers_license_num xsi:nil="true" />
  <gpa_highschool xsi:nil="true" />
  <created_dt>2006-07-13T11:15:08.320</created_dt>
  <created_how>4</created_how>
  <modified_dt>2008-02-14T00:00:00</modified_dt>
  <modified_by>4</modified_by>
  <primary_street2 xsi:nil="true" />
  <primary_street3 xsi:nil="true" />
  <primary_country xsi:nil="true" />
  <email_address xsi:nil="true" />
  <address_start_dt xsi:nil="true" />
  <address_end_dt xsi:nil="true" />
  <entrance_iv_dt xsi:nil="true" />
  <entrance_iv_by xsi:nil="true" />
  <exit_iv_dt>2006-11-02T00:00:00</exit_iv_dt>
  <exit_iv_by>156</exit_iv_by>
  <foreign_address_indicator>N</foreign_address_indicator>
  <foreign_postal_code xsi:nil="true" />
  <pin>J27841</pin>
  <web_id>J08614   </web_id>
  <prior_name xsi:nil="true" />
  <orig_eps xsi:nil="true" />
  <web_role>STU1</web_role>
  <heal_limit_flag>N</heal_limit_flag>
  <email_address_2>[email protected]</email_address_2>
  <cellular_telephone>415</cellular_telephone>
  <alt_loan_debt xsi:nil="true" />
  <web_last_login xsi:nil="true" />
  <foreign_country_code xsi:nil="true" />
  <entrance_iv_dt_grad_plus xsi:nil="true" />
  <entrance_iv_by_grad_plus xsi:nil="true" />
  <failed_logins>0</failed_logins>
  <hispanic xsi:nil="true" />
  <race xsi:nil="true" />
  <primary_phone_number_intl xsi:nil="true" />
  <security_version>0</security_version>
  <failed_challenge_response>0</failed_challenge_response>
  <require_pin_reset xsi:nil="true" />
</row>'

Using openxml.

declare @idoc int
exec sp_xml_preparedocument @idoc out, @xml, '<row xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"/>'

select FieldName, 
       FieldValue,
       isnull([IsNull], 0)
from openxml(@idoc, '/row/*',1) 
  with (
         FieldName  varchar(50) '@mp:localname',
         FieldValue varchar(50) '.',
         [IsNull]   bit         '@xsi:nil'
       )

exec sp_xml_removedocument @idoc

Using the XML data type:

;with xmlnamespaces('http://www.w3.org/2001/XMLSchema-instance' as ns)
select T.N.value('local-name(.)', 'varchar(50)') as FieldName,
       T.N.value('.', 'varchar(50)') as FieldValue,
       isnull(T.N.value('@ns:nil', 'bit'), 0) as [IsNull]
from @xml.nodes('/row/*') as T(N)