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Kimball Chapter 1, Database Normalization Review - Coggle Diagram
Kimball Chapter 1
Dimensional Modeling
Thinking business as Cube of data
Quote: "We sell products in various markets and measure our performance over time"
Edges of cubes labeled as
product, market, time
point inside the cube as
measurements
Different from 3NF model
3NF model
discrete entities as logical model
relational table as physical model
useful
operational/transational processing
not useful and performatic
BI queries
E-R (Entity Relationship) diagram
communicate relationship between tables
both 3NF and dimensional model
ER != 3NF model
normalized model = 3NF
difference relies on degree of normalization
Dimensional models
users undestandability
query performance
resilience to change
Star Schemas vs OLAP Cubes
start-schema
implemented in relational database management system (RDMS)
OLAP (online analytical processing) Cube
implemented in multidimensional database env
Data capture
vs. Data Analysis
information purposes
operational and transaction record keeping
analytical decision making
Data I/O
Data in: operational systems
performing the organization's business process
do not mantain history
update data to refletect the most current state
Data out: DW/BI system
answer business questions
high-performance queries
historical context data
Goals of Data Warehousing and BI
Requeriments: DW must
make info easily accessible
minimal waiting times
present info consistently
cleansed
quality assured
common labels and definitions
adapt to change
handle process and/or strategy changes (1P/2P; ILM etc.)
without change or disrupted the existing data
present info in timely away
raw data transformation within hours, minutes or seconds
keep data securely and control access
Database Normalization Review
Link Reference
attributive data or indirectly related data are put in different tables and these tables are connected with a logical relationship between parent and child tables.
Advantage
Disadvantages
1NF (First Normal Form)
2NF (Second Normal Form)
3NF (Third Normal Form)
