designing Olap cube dimensions and facts for population growth cube

Question

I want to create an Olap cube for Population Growth. I have a MySQL database with table:

 Act (
 id  INT NOT NULL AUTO_INCREMENT,
 birth_date DATETIME,
 death_date DATETIME,
 place VARCHAR(20)  
 );

and I want it to be my dimension for table Fact_Population_Growth. I want to analyze the number of births and deaths in a given time and place. However, as easy it may seem on paper, when using Pentaho Workbench for building olap cubes, I get pretty confused. Do I have only one dimension or do I have to do dimension time and dimension place? Are my measures number of births and number of deaths? Is there a way to store the difference between these two and in result have the population growth? Would this Fact_Population_Growth table do the job? :

 Population_Growth(
 id INT NOT NULL,
 number_of_births INT, 
 number_of_deaths INT,
 time DATE
 place VARCHAR,
 result INT  
 );

nsousa nsousa · Accepted Answer · 2014-06-12T15:17:11

There should be two dimensions, place and time, and two measures, the number of births and deaths.

designing Olap cube dimensions and facts for population growth cube

1 Answers