What are slowly changing dimensions?

Answer Posted / chaitanya

SCD, is a technique used to store the historical value of
dimension attributes.

The values of dimensional attributes change as time goes by.
When these attribute values change, you can overwrite the
old values with the new ones, or you can
preserve the old value.

There are two methods of preserving the old attribute
values: you can store the old values as rows, or you can
store them as columns

three types of SCD:
• SCD type 1 overwrites the old values of the attributes so
the old values are not kept.
Ex: In product dimension,we will use SCD type 1, meaning we
will overwrite the old attribute values.

SCD type 2 keeps the old values by creating a new row for
each change.
SCD type 3 keeps the old values by putting them in another
column

Is This Answer Correct ?    0 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Write the unconnected lookup syntax?

662


Briefly define a session task?

593


Describe data concatenation?

577


During the running session, output files are created by informatica server. Enlist few of them.

546


can i any one explain me realtime healthcare project explanation..for interview .iam new to informatica .thanks in advance.

3326






What is sorter transformation?

587


Describe the scenarios where we go for joiner transformation instead of source qualifier transformation?

621


Why filter transformation is an active one?

565


What will be the approach?

584


What are the databases that informatica can connect to windows?

587


Under what conditions selecting sorted input in aggregator will still not boost session performance?

638


How do you load only null records into target? Explain through mapping flow.

1509


What are the validations that you can perform in oracle and in informatica ? Advance Thanks

1660


How might one distinguish in the case of mapping is right or not without associating session?

642


i have a data in my source as a flat files what test i have to perform the next step can any body help to me

1702