Shredding XML to Tables While Providing Parent-Child Keys

In my last post, I demonstrated how to shape and bend XML from your existing tables in SQL Server. In this post I am going to go the other direction and shred the xml directly into SQL tables with a desired structure. I will also create a parent-child relationship between entities where no keys previously existed in the xml.

This approach uses the older OPENXML mechanisms and is distinct from the value() and node() methods introduced later. I believe this approach to be superior and easier to construct than that demonstrated by Adam Machanic.

  • I'm assuming here that you've loaded the xml into the @xmlDocument variable (as in my previous example)
  • You need a document handle (@XmlDocumentHandle). As long as this handle remains open, the id's returned for each node do not change.
  • Use the OPENXML function with the @XmlDocumentHandle and create an XPath query that finds the data for the you want.
  • The value of 9 means to map attributes to your defined table, and handles really big documents.
  • The table definition is in the WITH clause
  • The @mp:id and @mp:parent are the identifier for the individual node and its parent. Every node in the document has a unique value that doesn't change; these are used to make our parent-child relationships work.
Here is some sample XML and SQL:
And here are some results: (sorry for the ugly tables)
StudentIdIdFirstNameLastSurname
21322C606-D644-497B-8548-207933921855ShelbyBarajas
219F5B105B-0B03-4508-B7B4-AD1731A85B6ESarahStevens
395757B9B9-C4AD-4B6D-B1A0-056B2D08B7BDGilbertFritz
58DE2FF0BA-F23B-4323-87C9-FA4AF3C3FA44DebbieSavage
76AFE73075-5460-4FBD-858B-E8864E8E1A38SandroMiguel
9547E92DBE-AE26-4F52-B532-5F8BD9E02826AliciaDennis
AddressIdStudentIdStreetNumberName
142654 Mission Hills
3221123 Simons Way
513916 Green Hague Way
6958123 Simons Way
887616 Green Hague Way
1079525 North Clarendon Boulevard
LanguageIdStudentIdLanguageDescriptorId
11495524
LanguageUseIdLanguageIdLanguageUseTypeId
1161141

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