Role Playing dimension in Data warehouse

In last  few tutorial , we started talking about various Type of dimension in Data ware house  and what role they play in data warehouse.Last time  we talked about Conformed dimension and Junk Dimension . Data warehouse mainly consists of Dimension and Fact tables.   In below article we will go through the Role Playing Dimension in dataware house with some example , why they are important.Hope you will enjoy this small data warehouse tutorial.

Role PlayingDimension in Data warehouse

A dimension is Role playing dimension , with multiple valid relationships between itself and another table . This is most commonly seen in dimensions such as Time and Customer.

For example :In below Order Fact Table  , it has multiple relationships to the Date dimension on the keys Order_date ,shipping_date. Now to handle this situation instead of creating two separate dimension table we can create two views of original date dimensions table one is Order_date_dim and another is ship_date_dim

 

I found a good article on Role Playing dimension in data ware house here

I also found some good article on other various type of dimension as well.

• Conformed dimension 
• Junk dimension
• Degenerate Dimension

Junk dimension in Data warehouse

In last tutorial , we have gone through some of the basic concept of data warehouse , what exactly data warehouse store ,importance of data warehouse. We also saw various properties of  data warehouse. Data warehouse mainly consists of Dimension and Fact tables. We will go through different type of dimension mainly used in data warehouse in upcoming articles.  In below article we will go through the Junk Dimension in dataware house with some example , why they are important.Hope you will enjoy this small data warehouse tutorial.

Junk Dimension in Data warehouse

A junk dimension is grouping of low cardinality flags and indicators. This junk dimension helps in avoiding cluttered design of data warehouse. Provides an easy way to access the dimensions from a single point of entry and improves the performance of sql queries.

 For example : For example, assume that there are two dimension tables (gender and marital status). The data of these two tables are shown below:

I found a good article on junk dimension in data ware house here

I also found some good article on other various type of dimension as well.

• Conformed dimension 
• Degenerate dimension
• Role Playing Dimension