03 Information Needs Analysis and DWH Schema

Question 1

Mention some examples as needs for timely information:

Answer 1

Businesses need to work at an increasing pace:

• Customer request increasingly individual solutions
• Quicker reaction to market changes and competitors (real-time BI)
• Process-oriented way of working (end-to-end processes)
• Smart object populate the world (Internet of Things)
• Advanced analytics of large and complex data sources (BigData)

Question 2

Explain the model that describes information subsets (supply, requested…).

Answer 2

Main information subsets:

• Information supply = deliverable information.
  
  • Data available to be analyzed, compiled from data structures and/or reporting systems, reports, cubes, ratios, dimensions, reference objects.
  • Opportunities for optimization: find similarities, parameterized reports, eliminate unnecesary information objects.
• Objective information need = objectively needed to make decisions.
  
  • Sum of all data required to fulfill organization’s objectives.
  • Can be deducted from biz strategy and objectives, processes implemented, decisions of actors in the organization, external knowledge (reference models)
• Subjective information need = subjectively needed to make decisions.
  
  • Information requested by an individual, at a specific time to solve a decision problem in a specified quality, day-to-day decisions.
• Requested information = objective + subjective + deliverable (partially in every aspect)

Question 3

From where is the Objective Information needs being derived? name and explain those 2 sources.

Answer 3

Objective information needs have 2 sources:

• Business strategy = higher in importance, defines the “right things”, business top.
  
  • Top-level objectives: mission, vision, corporate identity, policies and practices.
• Operational objectives = easier to measure, inform if the “right things” are “right”, business bottom.
  
  • General goals, organizational and BU’s goals, marketing-mix-based goals, department objectives.
  • These operational objectives could be inconsistent and even incompatible (contradictory, success of one leads to failure of another).

* from Porter = the essence of strategy is in the activities. Operational objectives enable management to do the right things right.

Question 4

What is a Reference object?

Answer 4

Reference objects are:

• Business objects differentiated functionally and in terms of time.
• Objects that get financial and quantitative values attributed (can cause costs).
• “All measures, processes and states of affairs which can be object to arrangements or examinations on their own”.
• Subjects of business/management decisions.
• Examples:
  
  • Reference object spaces: Company, Region, Market Segment, Product line, Product.
  • Time-Month: Year, Quarter, Month, Day.
  • Time-Week: Year, Calendar week, Day.
  • Time-Day: Weekday, Day.

Question 5

What are the differences between the Star Schema and Snowflake Schema?

Answer 5

The Star Schema have every dimension connected to a central fact table.

The Snowflake Schema has a hierachy of dimensions connected to a central fact table.