W3C about XQuery: “XQuery is replacing proprietary middleware languages and Web Application development languages.” Just remember: XQuery is not just for querying XML!

1. XQuery Novelties
Geert Josten
Hardcore XML track
XML Holland
11 november 2010

2. Agenda
 Original Scope
 Extending Scope
 Newest Extensions
 Beyond Scope
 Summary
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3. about XQuery
“XQuery is replacing proprietary middleware
languages and Web Application
development languages.”
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4. About XQuery
“XQuery is replacing proprietary middleware
languages and Web Application
development languages.”
 Observation, glue
 More and more XQuery applications
 Beyond original scope
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5. Original scope
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6. Origin
 1999, XPath and XSLT not enough
 Query languages applied to XML
 SQL, OQL, Lorel, ..  XML-QL, XQL
XQuery
 Merged into Quilt
 XQuery WD in 2001
XQuery
XQuery
XQuery
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7. Origin
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8. Extending scope
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9. Database features
 Efficient storage and extraction  XQuery 1.0
 Searching
 Transactional updating
 Data integrity, Triggers
 Simultaneous access
 Security, Crash-recovery
 Optionally: Versioning
 ...
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10. XQuery and XPath Full Text 1.0
 First extension, 2004
 W3C Candidate Recommendation
 Search within specific nodes
 Advanced „contains‟ expressions
 Options
• stemming, wildcards, thesaurus, ...
 Relevance ranking
 Lot of implementations, few compliant
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11. XQuery Update Facility 1.0
 Introduced in 2006
 W3C Candidate Recommendation
 Updating of individual nodes:
 insert, delete, replace, rename, and transform
 No return values!
 Various implementations, partly compliant
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12. Newest extensions
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13. XQuery Data Definition Facility
 Presented at XML Prague 2010
 28msec and ETH Zürich
 Static declaration:
 collections, indexes and constraints
 Functions:
 Updating collections
 Probing indexes
 One implementation?
 Zorba / Sausalito
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14. Update compositions
 Presented at XML Prague 2010
 ETH Zürich and Oracle
 Storage cheap
 Keep all changes
 Consolidated changes aka composition
 Versions integral part of tree
 No implementations?
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15. Beyond scope
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16. XQuery Scripting Extension 1.0 (SX)
 W3C Working Draft since 2008
 Procedural constructs
 While, variable assignment, exit, ..
 Breaks functional approach
 Also allows multiple, incremental updates
 Update *and* return results
 Very useful for application logic
 Few implementations yet
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17. XQuery 1.1
 W3C Working Draft since 2008
 Lots of small improvements
 Improved FLWOR
 Try/Catch
 Dynamic function invocation
 Output declarations
 Mature language, design patterns
 Not many implementations yet
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18. XRX and NoSQL
 NoSQL:
 Use non-relational database
 Open source or open standard (like XQuery)
 XRX:
 Xforms + Rest + Xquery
 Innovative two-tier architecture
 XForms front-end, XQuery back-end,
REST api
 Breaking long-lasting traditions
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19. Summary
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20. Database features revisited
 Features covered:
 Extraction, Searching, Updating, Data constraints,
Versioning
 Functional in nature
 Uncovered:
 Storage, Security, Triggers, Crash-recovery..
 Mostly technical, necessary?
 More lacking?
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21. Just remember
XQuery is not just for querying XML!
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22. Questions?
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23. Timeline
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24. XQuery and XPath Full Text 1.0
Contains expression
for $b in /books/book Combined search
where $b/title
contains text "improving“ ftand "usability“
ordered distance at most 2 words at start
return
Advanced search criterium
$b
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25. XQuery Data Definition Facility
declare collection users as element()*;
declare automatically maintained index users-by-id
on nodes xqddf:collection( xs:QName(“users") )
by @id as xs:string;
xqddf:insert-nodes(
xs:QName(“users"), <user id=“geert”/> );
xqddf:probe-index-point(
xs:QName(“users-by-id"), “geert” );
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