Be confused with Outtrigger

View previous topic View next topic Go down

Be confused with Outtrigger

Post  magaret264 on Mon Nov 01, 2010 6:40 am

Hi experts,

I have refered to "The Datawarehouse Toolkit Olap Solutions - Chapter 6".
I'm confused how we track employee skills by using Outtrigger.

EMPLOYEE SKILL GROUP OUTTRIGGER as B
B.Employee Skill Group Key int PK
B.Employee Skill Category
B.Employee Skill Key varchar
B.Employee Skill Description

Data of B
1,DBA,MSSQL\ORALCE\MYSQL,rs1
2,DBA,MSSQL\ORACLE,rs2
3,DBA,ORACLE\DB2\CONGROS,rs3
4,BANKING,CASATD\CL,rs4


EMPLOYEE DIMENSION as A
A.Employee Key PK
A.Employee Attributes ...
A.Is_Available
A.Employee Skill Group Key FK


If employee E got skills belonging to 2 skill groups, which one will be our solution?
1.insert a new definition of skill group with into B. And E traking-record will have new Employee Skill Group Key. Then it looks like difficult to understand if both skill groups dont have any relationships

2.duplicate E tracking-data with 2 appropriate foreign keys with values of Is_Available = 1. Is it ok?

3.Then we answer the question: How many employees have got skill DBA of MSSQL and CONGROS? like [Employee Skill Key] LIKE %\MSSQL\% OR [Employee Skill Key] %\CONGROS\%
Or let's count employee bases on every specific skill --> how can we get the report?

Why dont we use dimension table containing skills with level for each skill? And fact table just constains foreign keys to tracking employee' skills. Although it makes the report clearer, I think it's not a good choice. With this way, we will have a set of records with the same "time key" reflecting current skills of an employee.

I'm sorry. I'm not good at English. And I'm newbe in DW design.


Thank you for your help!

magaret luong



Last edited by magaret264 on Mon Nov 01, 2010 10:00 am; edited 1 time in total (Reason for editing : 'm sorry. I'm not good at English.)
avatar
magaret264

Posts : 2
Join date : 2010-10-28

View user profile

Back to top Go down

Re: Be confused with Outtrigger

Post  Jeff Smith on Mon Nov 01, 2010 11:14 am

If all you need to do is answer, "how many employees have skill A?" then I would create a dimension table of Skills and the fact table would contain a row for Employee/Skill. If an Employee had 6 skills, they would be in the fact table 6 times - once with each of their skills.

Jeff Smith

Posts : 471
Join date : 2009-02-03

View user profile

Back to top Go down

Re: Be confused with Outtrigger

Post  magaret264 on Tue Nov 02, 2010 6:35 am

Jeff Smith wrote:If all you need to do is answer, "how many employees have skill A?" then I would create a dimension table of Skills and the fact table would contain a row for Employee/Skill. If an Employee had 6 skills, they would be in the fact table 6 times - once with each of their skills.

Hi Jeff,

I agree with you. I will modify my model following your suggestion.

Thank you!

avatar
magaret264

Posts : 2
Join date : 2010-10-28

View user profile

Back to top Go down

Re: Be confused with Outtrigger

Post  Sponsored content


Sponsored content


Back to top Go down

View previous topic View next topic Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum