Nagaraju Puppala

 Profile Answers by Nagaraju Puppala 

• Feb 9th, 2011

 

Yes,

You can create SCD1, SCD2 logic in a single mapping :)

Considersd Employe Table: which contains the columns eno, ename, sal, designation, phone, address.

while you are loading in to the warehouse table, we should use the SCD2 logic to maintain the historical records for required columns like sal, designation.

and for the updates on the source data on phone, address, no need to maintain the historical records. in this scenario we can simply overrite the data using SCD1 logic.


Means we are maintaing only the historical data of the required columns.

In the expression-lookup we can decide whether we need to insert the new(historical) record or update the existing record by considering the target data as well as the updated data while running the incremental load.
if the sal, designation columns are updated then we need to maintain the historical data, ie insert the new record(SCD2).

if the updates on only the columns address, phone then we can just updated the data(SCD1).

I hope you clear about it..

Cheers :)

Nagaraju Puppala

Nagaraju Puppala

 Profile Answers by Nagaraju Puppala 

• Feb 9th, 2011

 

Yes,,

We should use the both logics in a single mapping in the real time.


When an organization maintainig the employee data..

It should maintain all historical data like the salary, designations etc.

and if the employee changes the address/phone, we just update the records, no need to store the historical data,,

it depends on our requirement.


Cheers:)

Nagaraju Puppala