COMP20008 Study Guide - Final Guide: Interquartile Range, Recommender System, Pearson Product-Moment Correlation Coefficient
9 Jun 2018
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CVS vs Excel
CSV is flat file
Excel: operations, formatting
HTML vs XML
XML and HTML were designed with different goals:
• XML was designed to carry data - with focus on what data is
• HTML was designed to display data - with focus on how data looks
• XML tags are not predefined like HTML tags are
XML Namespace:
• Aim: to provide uniquely name element or attribute
• Avoid ambiguity, uniquely describe what I mean using the URL
• First look at its bracket first than look at it's parents or grandparents , NOT
SIBLING
XML attribute vs elements
Elements: to store information. Attribute identify elements.
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Some of the problems with attributes are:
• attributes cannot contain multiple values (child elements can)
• attributes are not easily expandable (for future changes)
• attributes cannot describe structures (child elements can)
• attributes are more difficult to manipulate by program code
• attribute values are not easy to test against a DTD
What I am trying to say here is that metadata (data about data) should be stored as attributes, and that
data itself should be stored as elements.
XML vs JSON
XML allows complex schema definitions (via regular expressions)
– allows formal validation
– makes you consider the data design more closely
JSON is more streamlined, lightweight and compressed
– Which appeals to programmers looking for speed and efficiency
– Widely used for storing data in noSQL databases
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find more resources at oneclass.com
XML schema: describe the structure of document
The purpose is to define the legal building blocks of an XML document: the
elements and attributes that can appear in a document, number of child
elements, data types
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Xml namespace: aim: to provide uniquely name element or attribute, avoid ambiguity, uniquely describe what i mean using the url, first look at its bracket first than look at it"s parents or grandparents , not. What i am trying to say here is that metadata (data about data) should be stored as attributes, and that data itself should be stored as elements. Xml allows complex schema definitions (via regular expressions) Makes you consider the data design more closely. Which appeals to programmers looking for speed and efficiency. Widely used for storing data in nosql databases. The purpose is to define the legal building blocks of an xml document: the elements and attributes that can appear in a document, number of child elements, data types. Name space has to be parents, not sibling. To measure data quality which are: accuracy, completeness, consistency, timeliness, believability.
