sendtorohit

 Profile Answers by sendtorohit 

• Oct 10th, 2011

 

Late arriving Fact table:

For example there was a credit card of transaction happened on 25th Mar 2005, but this record we received on 14th Aug 2007. During this period there is a possibility of change in dimensional data.

There are two table one is transaction fact table and customer dimensional table

Transactional fact table is having two time stamps
1. Transaction date
2. Load date

Customer dimensional table is having two time stamps

1. Enter date (when customer provided the details)
2. Load date

In case of late arrive fact records we have get the proper key from the dimensional tables as these tables are maintaining the history.

In above scenario we have to extract the right key by using transaction date <= enter date from customer dimension table for the particular customer.


Late arriving Dimension table:

This is very general practice in consumer finance projects
Some times we will get the transactional data without dimensional date. In this practice we will follow two methods.

1. Create one dummy record in dimensional table and join with fact table. Once we receive this data the dummy record in the Dim table will be updated using type SCD1
2. Place the transactional data in staging table till we receive the dim records. Re keying processed will be used to get the key from dim table