standards in information management xml

ISOM Standards in Information Management: XML Arijit Sengupta ISOM Learning Objectives • Learn what XML is • Learn the various ways in which XML is used • Learn the key companion technologies • See how XML is being used in industry as a meta- language ISOM Agenda • Overview • Syntax and Structure • The XML Alphabet Soup • XML as a meta-language ISOM Overview What is XML? • A tag-based meta language • Designed for structured data representation • Represents data hierarchically (in a tree) • Provides context to data (makes it meaningful)  Self-describing data • Separates presentation (HTML) from data (XML) • An open W3C standard • A subset of SGML  vs. HTML, which is an implementation of SGML ISOM Overview What is XML? • XML is a “use everywhere” data specification Documents Configuration Database Application X Repository XML XML XML XML ISOM Overview Documents vs. Data • XML is used to represent two main types of things:  Documents • Lots of text with tags to identify and annotate portions of the document  Data • Hierarchical data structures ISOM Overview XML and Structured Data • Pre-XML representation of data: • XML representation of the same data: “PO- 1234”,”CUST001”,”X9876”,”5”,”14.98 ” <PURCHASE_ORDER> <PO_NUM> PO-1234 </PO_NUM> <CUST_ID> CUST001 </CUST_ID> <ITEM_NUM> X9876 </ITEM_NUM> <QUANTITY> 5 </QUANTITY> <PRICE> 14.98 </PRICE> </PURCHASE_ORDER> ISOM Overview Benefits of XML • Open W3C standard • Representation of data across heterogeneous environments  Cross platform  Allows for high degree of interoperability • Strict rules  Syntax  Structure  Case sensitive ISOM Overview Who Uses XML? • Submissions by  Microsoft  IBM  Hewlett-Packard  Fujitsu Laboratories  Sun Microsystems  Netscape (AOL), and others… • Technologies using XML  SOAP, ebXML, BizTalk, WebSphere, many others… ISOM Agenda • Overview • Syntax and Structure • The XML Alphabet Soup • XML as a meta-language [...]... transforming XML documents XSL-FO XSL Formatting Objects Language to describe precise layout of text on a page The XML ‘Alphabet Soup’ ISOM XPath XML Path Language A language for addressing parts of an XML document, designed to be used by both XSLT and XPointer XPointer XML Pointer Supports addressing into the Language internal structures of XML documents XLink XML Linking Describes links between XML Language... ‘Alphabet Soup’ ISOM XML Extensible Markup Language Defines XML documents Infoset Information Set Abstract model of XML data; definition of terms DTD Document Type Definition Non -XML schema XSD XML Schema XML- based schema language XDR XML Data Reduced An earlier XML schema CSS Cascading Style Sheets Allows you to specify styles XSL Extensible Stylesheet Language Language for expressing stylesheets; consists... documents XQuery XML Query Language Flexible mechanism for querying (draft) XML data as if it were a database DOM Document Object API to read, create and edit XML Model documents; creates in- memory object model SAX Simple API for XML API to parse XML documents; event-driven Data Island XML data embedded in a HTML page Data Automatic population of HTML elements from XML data Binding The XML ‘Alphabet Soup’... Definitions)  Not written in XML  No support for data types or namespaces • XSD (XML Schema Definition)  Written in XML  Supports data types  Current standard recommended by W3C The XML ‘Alphabet Soup’ Schemas: Purpose ISOM • Define the “rules” (grammar) of the document  Data types  Value bounds • A XML document that conforms to a schema is said to be valid  More restrictive than well-formed XML. .. an XML Document ISOM • Elements  Each element has a beginning and ending tag •  Elements can be empty () • Attributes  Describes an element; e.g data type, data range, etc  Can only appear on beginning tag • Processing instructions  Encoding specification (Unicode by default)  Namespace declaration  Schema declaration Syntax and Structure Components of an XML. .. You can define your own entities • Parsed entities can contain text and markup • Unparsed entities can contain any data  JPEG photos, GIF files, movies, etc Agenda ISOM • Overview • Syntax and Structure • The XML Alphabet Soup • XML as a meta-language The XML ‘Alphabet Soup’ ISOM • XML itself is fairly simple • Most of the learning curve is knowing about all of the related technologies The XML ‘Alphabet... Namespaces: Declaration ISOM Namespace declaration examples: xmlns: bk = “http://www.example.com/bookinfo/ ” xmlns: bk = “urn:mybookstuff.org:bookinfo ” xmlns: bk = “http://www.example.com/bookinfo/” Namespace declaration Prefix URI (URL) Syntax and Structure Namespaces: Examples ISOM All About XML Joe Developer... nested  A tag must end within the tag in which it was started • Attributes are optional  Defined by an optional schema • Attribute values must be enclosed in “” or ‘’ • Processing instructions are optional • XML is case-sensitive  and are not the same type of element Syntax and Structure Well-Formed XML? ISOM • No, CHILD2 and CHILD3 do not nest properly ... XSD Example ISOM • XML document: All About XML Joe Developer … The XML ‘Alphabet Soup’ Schemas: XSD Example ISOM . ISOM Standards in Information Management: XML Arijit Sengupta ISOM Learning Objectives • Learn what XML is • Learn the various ways in which XML is used • Learn the key. technologies • See how XML is being used in industry as a meta- language ISOM Agenda • Overview • Syntax and Structure • The XML Alphabet Soup • XML as a meta-language ISOM Overview What is XML? • A tag-based. ISOM Overview What is XML? • XML is a “use everywhere” data specification Documents Configuration Database Application X Repository XML XML XML XML ISOM Overview Documents vs. Data • XML is used to