Lecture 23 & 24 Dimensional modeling and balanced scorecard

• Dimensional modeling Miscellaneous details
• Slowly changing dimension
• Purpose: Changes happen in attribute's value over time (e.g. brand, department, …), but don't happen frequently, rather happen once a while
• Type 0: nothing is ever going to change (this is not typical)
• Type 1: directly update attributes, completed lose history but simple
• Type 2: in order to preserve history, split tables
• Every time value of attribute change, add a new tuple with a new surrogate key, add start time and end time to the new tuple
• Type3: make changes to the table, Add a new column/new attribute called "new" territory, and change the previous one as "old" territory
• Rule playing dimension
• Junk dimension
• Put data altogether
• Semi-additive
• Non-additive: average, minimum, maximum, can't add together, e.g. balance of bank statement

• Balanced scorecard 
• use a bunch of factors to evaluate company
• Balancing different measurements to come up the overall performance
• Can be applied to any level of company
• BI is all related to performance management, which is the core function of balanced scorecard
• 4 perspectives (interacting with each other, the rest 3 factors are all linked back to finance)
• Finance: how well are the company doing respective to shareholder
• Customer
• Internal process: align with business
• Learning & growth

• After evaluating the company via balanced scorecard, we can clearly know performance of company in different fields, allowing us to draw Strategy maps to understand How we are going to achieve goals