Adv Databases

Question 1

What is XML used for?

Answer 1

Data communication, data sharing, patching and for separating HTML

Question 2

What is a Namespace?

Answer 2

XML namespaces are used for providing uniquely named elements and attributes in an XML document

Question 3

Namespace - how would you differentiate a element?

Answer 3

and

Question 4

What is the DOM

Answer 4

Programming standard for manipulating XML documents (Dom plays with Doc)

Question 5

Define XML Schema

Answer 5

A document defining elements to ensure a set of rules are implemented to the XML. An example is an Occurrence Indicator to declare the maximum number of elements

Question 6

Name the three group of Indicators

Answer 6

Order, occurrence and group

Question 7

What is XPATH?

Answer 7

A way of referring to the contents of an XML document

Question 8

What is RDF?

Answer 8

Resource Description Framework is a method of describing resources that can be easily read by computers

Question 9

What is the difference between a well formed XML document and a valid XML document?

Answer 9

Valid is readable by humans and well formed is readable by computers

Question 10

What is SPARQL

Answer 10

Current querying language for RDF

Question 11

What is URI?

Answer 11

Web scope identifier that can be used to identify any resource

Question 12

What is a literal?

Answer 12

Set of lexical values

Question 13

What is a blank node?

Answer 13

Locally scoped identifier for resources that are not otherwise named

Question 14

What does a triple consist of?

Answer 14

Subject, predicate, object

Question 15

What is a prefix?

Answer 15

An abbreviation of a URI

Question 16

Define OWA?

Answer 16

Open world assumption assumes that data is incomplete

Question 17

What two standards were introduced to add additional, well-defined vocab for RDF?

Answer 17

RDF schema and Web Ontology Language

Question 18

What does an RDF class allow for?

Answer 18

Simultaneous typing of resources. A RDF class is an ER entity

Question 19

What is taxonomy?

Answer 19

A classification schema for a vocabulary

Question 20

Why are there distributed databases?

Answer 20

For data protection laws, redundancy, performance, merging organizations.

Question 21

What is replication in distributed databases?

Answer 21

Where the DB stores some data at every node.

Question 22

What is synchronized replication in distributed databases?

Answer 22

Every node is kept up to date after every transaction

Question 23

What is asynchronized replication in distributed databases?

Answer 23

Every transaction is held in a queue

Question 24

What is key for performance management?

Answer 24

Good design, efficient connection management and properly formed SQL

Question 25

What is the three tier architecture?

Answer 25

Client –> Application Server –> Database

Question 26

What is connection pooling and name one benefit.

Answer 26

Recycling connections which can save time when querying in the future.

Question 27

Why is a cursor bad?

Answer 27

Takes up memory and locking

Question 28

What is Autotrace?

Answer 28

Debugging mechanism that gives an execution part of optimizer and statement execution stats

Question 29

What is metadata?

Answer 29

Data which is about data!

Question 30

What are the two types of metadata?

Answer 30

Structural (how the data is stored) and Descriptive (information about the data itself)

Question 31

True or false - Everyone should be able to see metadata

Answer 31

FALSE! Metadata should be kept a secret

Question 32

What is a distributed database?

Answer 32

DB with more than one DBMS