DDMA Level II
Warehousing and Data Mining glossary
Every term this guide defines, A to Z, each with the chapter that teaches it. Open it when a word in a question is unfamiliar, and test yourself on it in the last week: cover the definition and say it in one sentence.
13 terms from the free first chapter
D
- Data warehouses
Optimised for large, complex read-heavy queries over historical data, analysis rather than transaction processing.
Taught in Warehousing and mining concepts
- Drill-down
The reverse, moving to a more detailed level, e.g. from monthly down to daily.
Taught in Warehousing and mining concepts
E
- End-user access tools
Reporting, analysis and visualisation tools end users interact with directly.
Taught in Warehousing and mining concepts
F
- Fact constellation schema
Multiple fact tables sharing dimension tables, supporting more complex, multi-subject analysis.
Taught in Warehousing and mining concepts
L
- Load manager
Performs the operations needed to extract and load data into the warehouse.
Taught in Warehousing and mining concepts
O
- OLTP systems
Optimised for many small, fast read/write transactions, day-to-day operational processing, e.g. a point-of-sale system.
Taught in Warehousing and mining concepts
P
- Pivot (rotate)
Reorients the data's dimensions to view it from a different perspective.
Taught in Warehousing and mining concepts
Q
- Query manager
Manages user queries, directing them efficiently to the right data.
Taught in Warehousing and mining concepts
R
- Roll-up
Aggregates data to a higher, less detailed level, e.g. from daily to monthly sales.
Taught in Warehousing and mining concepts
S
- Slice and dice
Selecting a subset of the data (slice) and viewing it from different angles (dice).
Taught in Warehousing and mining concepts
- Snowflake schema
Extends the star schema by normalising dimension tables into sub-dimensions, saving storage at the cost of more complex queries.
Taught in Warehousing and mining concepts
- Star schema
A central fact table connected directly to denormalised dimension tables, simple and fast to query.
Taught in Warehousing and mining concepts
W
- Warehouse manager
Manages the data once it is in the warehouse, organising, archiving and maintaining it.
Taught in Warehousing and mining concepts
The full glossary adds every term from the other 4 chapters, A to Z, each with the chapter that teaches it.