21. What is XLink and XPointer?
XLink is the standard way of creating hyperlinks in the XML files. Xpointer which allows those hyperlinks to point to more specific parts of the XML file or document.
22. What is XQuery?
XQuery was designed to query XML data which is nothing but SQL for database tables. XQuery is used to fetch the data from the XML file.
23. What are nested elements in XML?
If one or more elements are nested inside the root element is called nested element. Nesting can be easy to understand and also keeps order in an XML document.
24. Why XSLT is important for XML?
XSLT is abbreviated as eXtensible Sytlesheet Language Transformation which is used to transform an XML document to HTML before it is displayed to the browser.
25. What is DTD?
DTD is abbreviated as Document Type Definition and it is defined to build legal building blocks of an XML document. It defines the XML document structure with elements and attributes.
26. What are the disadvantages of XML?
Following are the disadvantages of XML:
• XML will be just a text file if elements and attributes are not defined properly.
• Overlapping markup is not permitted
27. What are the benefits of XML?
Benefits of XML are
• Simple to read and understand
• XML can be done with a text editor
• Extensibility – No fixed tags
• Self – descriptive
• Can embed multiple data types
28. How can I include conditional statements in XML?
We cannot include conditional statement as like programming language.
<foo if{DB}="A">bar</foo>
This can be done by using Document Type Definition(DTD
<xsl:if test="@foo=’bar’">
<xsl:text>Hello, world!</xsl:text>
</xsl:if>
29. Can I replace HTML with XML?
No, XML is not a replacement of HTML. XML provides an alternative approach to define own set of markup elements, and it is used for processing and storing data.
30. Whether graphics can be used in XML? If so, How?
Yes, Graphics can be included in XML by using XLink and XPointer specifications. It supports graphic file formats like GIF, JPG, TIFF, PNG, CGM, EPS and SVG.
XLink:
<description
xlink:type="simple"
xlink:href="http://show.com/Cinema.gif"
xlink:show="new">
</description>
XPointer:
<description
xlink:type="simple"
xlink:href="http://show.com/Cinema.gif#Shownumber"
xlink:show="new">
</description>
31. What software is available for XML?
There are thousands of programs available for XML and updated list will be present in http://xml.coverpages.org.
32. What are the special characters used in XML?
<, > and & are the special characters used in XML. Because these characters are used for making tags.
33.Can I execute a XML?
No, we cannot execute XML, and it is not a programming language to execute. It is just a markup language to represent the data.
34. What is SGML?
SGML is large and powerful Standard Generalized markup Language which is used to define descriptions of the structure of different types of electronic document.
35. Why XML has been used for development?
XML is used for development for following reasons:
• Used for Database driven websites
• Used to store data for e-commerce websites
• Used to transport and store data on internet
• XML is used for database and flat files
• Generate dynamic content by applying different style sheets
