1 / 13

XML and XML in DLESE

XML and XML in DLESE. Katy Ginger November 2003. XML Purpose. Provide a container for data that is presentation and platform independent Container for data that is flexible and extensible; user defines the tags and content

ferris-scott
Download Presentation

XML and XML in DLESE

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. XML and XML in DLESE Katy Ginger November 2003

  2. XML Purpose • Provide a container for data that is presentation and platform independent • Container for data that is flexible and extensible; user defines the tags and content • A single container for data that has multiple purposes and uses in a variety of software or web applications Note: XML databases exist now

  3. What is XML data? • Is called instance documents • Consists of user defined tags • Is well-formed and valid • The content that can be defined and controlled See DLESE Annotation Metadata Record example

  4. Built-in Primitive Types • Strings: e.g. strings • Binary: e.g. boolean • Numeric: e.g. decimal, float, double from which integer is derived • Date/time: e.g. date, dateTime, duration, time

  5. Correct <car> <make>Dodge</make> <model>Spirit</model> <year>1994</year> <owner> <name>you</name> <plate>CO</plate> </owner> </car> Incorrect <car> <make>Dodge</make> <model>Spirit</model> <year>1994 <owner> <plate>CO</plate> <name>you</name> </car> </owner> Well-formed and valid XML

  6. DTD: Document Type Definition Describe the elements of XML instance documents Not well-formed XML Some data-typing Namespaces harder to deal with Schemas Describe the elements of XML instance documents Well-formed XML Strong data-typing Namespaces are easier to deal with DTD, Schemas & Namespaces Namespace: Collection of related element names identified by a name label (e.g. dc:title where dc is for Dublin Core)

  7. XML Schema Design Philosophy • Decide where to apply XML, it’s good for: • Data archiving • Message passing • Presentation documents • Decide between global & local XML declarations • Russian Doll Design • Salami Slice Design • Venetian Blind Model

  8. Russian Doll Design • Schema mirrors structure of the instance doc • Elements are declared inside parent elements • All elements are local in scope • Elements may appear multiple times but can’t be referenced elsewhere • Changes on an element affect only the content model (parent element) of the element being changed • Hides namespace complexities

  9. Salami Slice Design • Each element/attribute is declared globally • Content models are then pieced together through references • Elements can be used anywhere and in multiple schemas • Changes on an element affect it everywhere the element is used • Does not hide namespaces

  10. Venetian Blind Model • Elements/attributes are defined as types (simple or complex) • Content models are made of types • Types are reusable and extendable • Changes on an element affect its type and where the type is used • Namespaces can be hidden or not hidden

  11. How to control tag content • Use restriction and enumeration elements • Use regular expressions See DLESE Annotation Metadata Record example

  12. How DLESE uses XML • DLESE systems act on metadata • All DLESE metadata is stored as flat XML files • DLESE harvests metadata XML files from other digital libraries • DLESE provides metadata XML files to other digital libraries • DLESE transitioned to schemas in Spring 2003 • DLESE schemas use the Venetian Blind Model

  13. XSLT (Extensible Stylesheet Language Transformation) • Acts on valid and well formed XML documents like instance docs and schemas • Used to create new text, HTML or XML docs • DLESE uses it to crosswalk our metadata format to the Dublin Core metadata format

More Related