1. Friday, September 4 th, 2009 The Systems Group at ETH Zurich XML and Databases Exercise Session 5 courtesy of Ghislain Fourny/ETH © Department of Computer Science | ETH Zürich

2. Friday, September 4 th, 2009 PUL Algebra Theory Good to know: XML and Data Models 2 This is text. Physical view (syntax)

3. Friday, September 4 th, 2009 PUL Algebra Theory Good to know: XML and Data Models 3 This is text. Physical view (syntax) Logical view (data model) a a d d This is c c b b.. text e:f

4. Friday, September 4 th, 2009 PUL Algebra Theory Data models around 4

5. Friday, September 4 th, 2009 PUL Algebra Theory Data models around  Information Set (Infoset) http://www.w3.org/TR/xml-infoset/  Post Schema-Validation Infoset (PSVI) http://www.w3.org/TR/xmlschema11-1/  XQuery 1.0 and XPath 2.0 Data Model (XDM) http://www.w3.org/TR/xpath-datamodel/ 5

6. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 1: XQuery Data Model  Main features of the XDM: 6

7. Friday, September 4 th, 2009 PUL Algebra Theory  Main features of the XDM:  Instances are sequences of items  An item is an atomic item or a node among seven kinds (,,,,, ) Exercise 1: XQuery Data Model 7 =( )((, ), )=(,, )

8. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 1: XQuery Data Model  Main features of the XDM:  Instances are sequences of items  An item is an atomic item or a node among seven kinds: -Document node -Element node -Attribute node -Text node -Comment node -Processing instruction node -Namespace node 8 With XPath 2.0, namespace nodes become deprecated, and they are not available at all in XQuery 1.0.

9. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 1: XQuery Data Model  Main features of the XDM:  Instances are sequences of items  An item is an atomic item or a node among seven kinds  Why?  Allows to decompose and reuse expressions  XML is ordered! 9 In XQuery, anything that goes into or comes out of an expression is a sequence of items!

10. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 1: XQuery Data Model 10 In XQuery, anything that goes into or comes out of an expression is a sequence of items! Expression for if then else where order by while any every let return exit with = +

11. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 1: XQuery Data Model  Differences with Infoset: 11

12. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 1: XQuery Data Model  Differences with Infoset:  Sequences of items (again!)  Simple and complex types – (almost) no types in Infoset  If no validation, xs:untyped 12 The only types in Infoset are attribute types from the DTD.

13. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: Infoset 13

14. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: The 11 Information Items  Document  Element  Attribute  PI  Namespace  Character  Comment  Unexpanded Entity Reference  DTD  Unparsed Entity  Notation 14

15. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: The 11 Information Items  Document  Element  Attribute  Processing Instruction  Namespace  Character  Comment  Unexpanded Entity Reference  DTD  Unparsed Entity  Notation 15 These seven ones are easy to remember, right?

16. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: Document Information Items 16 Document Information Item [children] Element Information Item metadata [document element] Element Information Item metadata [notations] empty [unparsed entities] empty [base URI ].../info.xml [character encoding scheme] UTF ‐ 8 [standalone] [version] 1.0 doc

17. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: Element Information Items 17 Element Information Item metadata [namespace name] http://www.systems.ethz.ch [local name] metadata [prefix] dc [children] Element Information Items title, publisher [attributes] empty [namespace attributes] Attribute Information Item namespacedc [in ‐ scope namespaces] Namespace Information Items namespacedcsystems, xml [base URI].../info.xml [parent] Document Information Item metadat a

18. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: Element Information Items 18 Element Information Item title [namespace name] http://www.systems.ethz.ch [local name] title [prefix] dc [children] Character Information Items, as many as characters in "Systems Group" [attributes] Attribute Information Items lang, year [namespace attributes] empty [in ‐ scope namespaces] Namespace Information Items namespacedcsystems, xml [base URI].../info.xml [parent] Element Information Item metadata title

19. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: Attribute Information Items 19 Attribute Information Item namespacedc [namespace name] http://www.w3.org/2000/xmlns [local name] dc [prefix] xmlns [normalized value] http://www.systems.ethz.ch [specified] true [attribute type] (no DTD!) [references] unknown [owner element] Element Information Item metadata namespacedc

20. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: Attribute Information Items 20 Attribute Information Item lang [namespace name] http://www.w3.org/XML/1998/namespace [local name] lang [prefix] xml [normalized value] "en" [specified] true [attribute type] (no DTD!) [references] unknown [owner element] Element Information Item title lang

21. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: Attribute Information Items 21 Attribute Information Item year [namespace name] empty [local name] year [prefix] empty [normalized value] "2008" [specified] true [attribute type] (no DTD!) [references] unknown [owner element] Element Information Item title year

22. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: Namespace Information Items 22 Namespace Information Item namespacedcsystems [prefix] dc [namespace name] http://www.systems.ethz.ch Namespace Information Item xml [prefix] xml [namespace name] http://www.w3.org/XML/1998/namespace namespacedcsystems xml

23. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 2: Infoset - the tree 23 doc metadat a namespacedc title namespacedcsystems xml ETH Zurich e:f publisher lang year Systems Group namespacedcsystems xml namespacedcsystems xml

24. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI  What does PSVI have, which Infoset has not? 24

25. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI  What does PSVI have, which Infoset has not?  Schema Type information! 25

26. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 26 Target Namespace This is new. We have a target namespace for the schema. All global elements and types will be in this namespace

27. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 27 And with this attribute, even nested elements will be in the target namespace.

28. Friday, September 4 th, 2009 PUL Algebra Theory OXYGEN TUTORIAL 28

29. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 29

30. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 30

31. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 31

32. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 32

33. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 33

34. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 34

35. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 35

36. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 36

37. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 37

38. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: A schema 38

39. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 39 This is how you associate the schema with the document if there is a target namespace.

40. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 40 For metadata: [type definition type] [type definition namespace] [type definition anonymous] [type definition name]

41. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 41 For metadata: [type definition type] complex [type definition namespace] http://www.systems.ethz.ch [type definition anonymous] false [type definition name] metadata ‐ type

42. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 42 For title: [type definition type] [type definition namespace] [type definition anonymous] [type definition name]

43. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 43 For title: [type definition type] complex [type definition namespace] http://www.systems.ethz.ch [type definition anonymous] true [type definition name]

44. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 44 For publisher: [type definition type] [type definition namespace] [type definition anonymous] [type definition name]

45. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 45 For publisher: [type definition type] simple [type definition namespace] http://www.w3.org/2001/XMLSchema [type definition anonymous] false [type definition name] string

46. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 46 For xml:lang [type definition type] [type definition namespace] [type definition anonymous] [type definition name]

47. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 47 For xml:lang [type definition type] [type definition namespace] [type definition anonymous] [type definition name] From xml.xsd

48. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 48 For xml:lang [type definition type] simple [type definition namespace] http://www.w3.org/XML/1998/namespace [type definition anonymous] true [type definition name]

49. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 49 For year: [type definition type] [type definition namespace] [type definition anonymous] [type definition name]

50. Friday, September 4 th, 2009 PUL Algebra Theory Exercise 3: PSVI 50 For year: [type definition type] simple [type definition namespace] http://www.w3.org/2001/XMLSchema [type definition anonymous] false [type definition name] integer

51. Friday, September 4 th, 2009 PUL Algebra Theory What you should remember today  Data models interpret XML data at a logical level  Infoset (with or without a DTD)  PSVI (after an XML Schema validation)  XDM (before or after XML Schema validation)  Now that we have data, we can process it! 51

52. Friday, September 4 th, 2009 PUL Algebra Theory 52 Hope to see you next week!