Types of Dimension Tables in SSAS

Dimension Tables Types
Dimension table contains the master data information. A dimension table has a primary key column that uniquely identifies each dimension record. The dimension table is associated with a fact table using the primary key.

confirmed dimension — The value will be refered by more than one dimension table
junk dimension — Combined values of transaction
degenerate attribute — If a dimension data kept on a fact table for reference
Role Playing Dimension — Date dimension which act as a orderdate dimension and purchasedate dimension.

Types of Dimension Tables in SSAS was last modified: October 5th, 2017 by Justin Antony

Types of measures/facts tables

Fact Table Types

Fully Additive Facts: This measure which can be added across all the associated dimensions.
Example: sales amount is a fact which can be summed across different dimensions like customer, geography, date, etc.

Semi-Additive Facts: These are facts which can be added across only few dimensions.
Example: bank balance is a fact which can be summed across the customer dimension but it cannot be added across the date dimension

Non-Additive Facts: These are facts which cannot be added across any of the dimensions in the cube.
Example: profit margin is a fact which cannot be added across any of the dimensions. we can not add against product dimension.

Derived Facts: Derived facts are the facts which are calculated from one or more facts,
For example: profit margin.Which is calculated when needed

Factless Facts: Fact table will not have a measure they will have only the key values(Foreign key) refered to the dimension are called factless fact table.

Types of measures/facts tables was last modified: October 1st, 2017 by Justin Antony

What are types of storage modes in OLAP?

OLAP storage modes
There are three standard storage modes in OLAP they are
1.MOLAP — the data and aggregations are stored in a multidimensional format
2.ROLAP — data and aggregations are kept in the relational database instead of on the OLAP server
3.HOLAP — HOLAP is a combination of MOLAP and ROLAP HOLAP stores the detail data in the relational database but stores the aggregations in multidimensional format

What are types of storage modes in OLAP? was last modified: October 1st, 2017 by Justin Antony