What is ETL & Datawarehouse?

You probably heard about datawarehouses &Product_code: Shoes A Code_Branch: South ...". This
analysis tools in the past in database relatedis not meaningful for a report containing information, not
discussions or in job meetings.only raw data that can not answer complex business
The fact is that everyday more and more companiesquestions which would allow us to make a manager
are starting to think (and build) data warehouses ordecision.
other data analysis and statistical tools.These and a few other points are the key reasons to
It is no more a large-companies-only matter; today withbuild a datawarehouse to do analysis.
the right knowledge and expertise (or a little education)So how I move or copy the data from my everyday
small companies can also make analysis and gettransactional database to my datawarehouse?
valuable information to boost sales or revenues.Here is where ETL comes to play.
So what is a datawarehouse?ETL is the process for Extracting, Transforming and
In simple words, a Datawarehouse is a commonLoading data from one database to another.
repository (a database, for simplicity) of informationThere are several ways for doing this, from coding
about a company's activities and operations.your own processes to the more often used way of
This means, all your company's transactions such asimplementing ETL tools.
sales, payments or acquisitions end up in the dataThese ETL tools can do the job very well, and if
warehouse.chosen wisely can save you a lot of coding efforts
This "database" is a technical product or platform thatand money, since you can graphically build processes
allows us to "ask" real life business questions such asand in most cases without knowing how to program
"which branch sold more products this month?" orfor databases.
"who is my top performing salesman?"There are a lot of ETL tools in the market right now.
You may be thinking "I currently HAVE a databaseAs and advice, I suggest you to invest some research
which records sales/transactions/movements of mytime (and testing if possible) before choosing the one
company everyday".that suits your company's needs.
Yes, of course you have one of those. But that is aThey can range from open source free tools to high
transactional database. This means that this databaseprice commercial tools. Neither of them is perfect in
is heavily used everyday to store our company'severy situation, and you will have to take into account
operations, and because of this we cannot use it foryour data volumes, the analysis and answers you
analysis.want from your datawarehouse, and the periodicity
Also, this database holds data, not information.needed of those answers, among other aspects.
A typical example for a record would be "Qty:1