(This is an idea shared from my co-worker Ivan Li)
There are many tools to develop ETL. This document shares a new idea to develop light weighted ETL with Cognos Framework manager. This solution could be very useful for following situations:
1) You
want to quickly develop a prototype to transform data.
2)
You don’t use traditional DW
surrogate key in fact table, instead, you want to simply use natural business
key to connect dimensions and facts.3) Each table has many columns.
The
major advantage of FM solution is to allow modellers to focus on business logic
instead of detail coding. In addition, it will give us a good overview in term
of logic. It refers to follows:
1) What
source tables are needed?
2)
What relationship should be
built between these tables, such as left join?3) What filters are needed?
4) How many steps you want to transform the data?
5) What columns should be exist in target table?
A
sample overall picture looks like follows, same as traditional FM.
You can also make query with complicated logic as query subject.
when
generate SQL script in FM, make sure to fix the more-than-30-character issue,
delete the FM generated column such as c122.
Populate Data with the same SQL script
You
can make SQL script with good format with different SQL format tool.
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