XML and ADO.NET Questions and Answers

Answer: D

Correct answer: SOAP was an early form of XML.

SOAP is not a form of XML but a protocol expressed in it, and it postdates XML rather than preceding it. The other three statements are correct: it originally stood for Simple Object Access Protocol, it was defined for remote procedure calls over the internet, and the acronym has since been dropped.

Answer: B

Correct answer: True

A schema defines the content and the structure - which elements and attributes may appear, of what types, in what order and how often. Format, in the sense of how the document is to be presented, is not part of it; that is the business of XSLT, and keeping the two separate is one of the central ideas of XML.

Answer: C

Correct answer: SGML.

SGML is the general markup language from which both HTML and XML descend: HTML as one particular application of it, defining a fixed vocabulary of tags for documents on the web, and XML as a simplified subset of SGML for defining vocabularies of one’s own. XHTML is the reformulation of HTML in XML syntax.

Answer: A

Correct answer: True

XML combines the two traditions: it carries the hierarchical, self-describing structure of a document, and it can be generated from and loaded into a relational database. That double character is why it became the standard for interchange - a document is readable on its own terms and a database can still get at what is inside it.

Answer: A

Correct answer: True

The stylesheet holds the transformation rules, each matching a pattern in the source document and specifying what to produce for it. Supplying a different stylesheet materialises the same content in a different form, which is exactly the separation of content from format that XML is built around.

Answer: B

Correct answer: type-valid.

A document is type-valid when it has a DTD or schema and conforms to it. If it has one and breaks it, it is not-type-valid; if it has none, it is also not-type-valid by definition, since there is nothing to be valid against. A document may still be well-formed - correctly nested and tagged - without being type-valid.

Answer: B

Correct answer: {item, action}.

An XSLT stylesheet is largely literal output: the processor copies whatever it finds through to the result until it meets a command, which takes the form of an item to be matched together with the action to be taken on it. That structure is what makes XSLT declarative - the stylesheet says what to do when a pattern is found, not the order in which to look.

Answer: B

Correct answer: DTD.

A Document Type Declaration defines the structure a class of documents must follow - which elements may appear, in what order, and with what attributes. A document conforming to it is type-valid. The DTD begins with the keyword DOCTYPE, which is why that word is a plausible but wrong answer to this question.

Answer: C

Correct answer: DOCTYPE.

The declaration opens with <!DOCTYPE followed by the name of the root element and the definition or a reference to it. #PCDATA appears inside the declaration to indicate parsed character data, and neither of the other two words plays any part in a DTD.

Answer: D

Correct answer: With XML, all of the above are true.

All three hold and together they are why XML matters for database work. A document may contain more than one multi-valued path, which a relational view cannot; documents can be generated from database data; and data can be extracted from documents back into a database. The traffic runs both ways, which is the hybrid character of the technology.