You are creating a SQL Server Integration Services (SSIS) package that implements a Type
3 Slowly Changing Dimension (SCD).
You need to add a task or component to the package that allows you to implement the SCD
logic.
What should you use?
A.
a Data Conversion component
B.
an Execute SQL task that executes a MERGE statement on the database
C.
a Merge component
D.
an Expression task
Explanation:
Note: Type of Slowly Changing Dimensions
Slowly Changing Dimensions are categorized into three types named: Type 1, Type 2, and
Type3. The Type 1 SCD does not maintain the history of changing attributes, it overwrites
values of the attributes. Type 2 maintains historical values for changing attributes. Type 3
that we do not use much maintains separate columns for changed attributes. SSIS SCD
wizard supports both Type 1 and Type 2.
Using MERGE instead of SCD wizard
Replacement of SCD wizard with MERGE is not a straightforward technique. If the SCD has
both Type 1 and Type 2 types attributes, they need to be handled separately.
I think that “B” is the answer
If you did B, you wouldn’t need the SCD component generally. This whole thing is stupid, its for people who cant program to program with pictures. That’s why it’s C.
It can’t be Merge component, it would have to be merge join with the proper coalesce expressions. It’s B. B works here.