1. Health & Human Services Data Warehouse Why a Data Warehouse

2. What about the Client Index? The Client Index is an application that looks up individual Client’s within Health & Human Services. The Client Index has limited reporting capability that can be slow when aggregating data.

3. Client Index vs. Data Warehouse Client Index Centers around client’s activities Individual data 2 dimension reports –Age by System Slow aggregate reports “Cut-n-paste” into other applications Data Warehouse Centers around business facts Aggregated data Multi-dimensional reports –Age by Race by Program Fast reports 3 rd party reporting tools can be used.

4. Measures “facts” not activities Facts are business performance measurements –Meals provided –Dollars expended –Hours worked Facts are numerical and additive –Sum of dollars spent –Count of clients served Facts are stored in a “fact table” –Each row represents a measurement at a particular “grain”

5. What is a “grain”? The grain refers to the level of detail at which a business fact is stored Different businesses have different fact needs –A Social Services grain could be the number of food stamp dollars given to a case each month –In-Home Support Services grain could be the number of hours of service a client received in a provider’s pay period

6. Multi- dimensional view A dimension is a textual description that relates to a fact, for example: –Ethnicity (White, Black, Japanese) –Language (English, Spanish, Tagalog) –Gender (Male, Female) –Country (USA, Mexico, Canada) State (California, Arizona, New Mexico)

7. Used in Queries Dimensions are used to restrict and frame queries on facts, for example: “Give me a count of all Spanish speaking white males in California” The fact is the count (a number) The dimensions are: –spanish (language), –white (race), –male (gender), –and California (state)

8. Answers Business Questions How many Spanish speaking clients did H&HS serve in each department for each of the past 3 years? Which cities currently have the highest concentration of Asian clients? What has the trend been? How many people who receive Medi-Cal received a service in 2003 from health services, by service?

9. What makes a Data Warehouse?

10. Bus Matrix A matrix which is used identify and document the intersections between business process and common dimensions Each business process represents a row in the matrix and each dimension a column

11. Bus Matrix for H&HS

12. Where do we begin? Choose the systems to include Identify the exact grain of the business process Identify the dimensions available for use with each fact table row Choose the numeric facts of what is being measured

13. Key to Success To ensure success end user involvement is required: Data warehouse success is tied directly to user acceptance. If the users haven’t accepted the data warehouse …then your efforts have been exercises in futility. (Kimball, 2002)