I’ve noticed a fair bit of search traffic focusing on cost questions, particularly which is cheaper; a series of data marts or a single enterprise data warehouse.  I think it’s a bit like the question of lease vs buy.  Starting off building a single departmental data mart will represent a much smaller cash flow out.  But by the time you’ve built all the data marts, and then have to redo them all again to integrate between subject areas and departments, I’d have to say that I’m with Bill Inmon when he says no number of data marts add up to a data warehouse.

With data marts (just like leasing a car) you get behind the wheel quickly, and it gets you where you want to go in style.  And the monthly payment is something you can afford now.  However, long term, well, in three years you don’t own it, and have paid a bundle.

But let’s be realistic.  Just as having all the cash on hand to buy the car outright just might not be in the cards,  a true data warehouse might require a very significant outlay before anything comes out the other end, making it unaffordable.  A quick, focused departmental data mart could be delivering value in a matter of weeks with relatively little investment.  (Your actual mileage may vary- depending on where you’re at, its always dangerous to believe someone when they say “a matter of weeks” when software and people are involved.)

Will that departmental data mart, or even a number of data marts lead you to a single version of the truth?  Will it give you deep competitive advantage through a culture of data analytics and cross enterprise master data management? In my honest opinion, No.

But is it something you can afford in today’s economy, and will you learn things about your data, your company’s information culture, and your business that will be useful if in the future you embark on a true data warehouse initiative.  Yes.  Yes it is, and yes you will.

And I’ll take it one (blatantly promotional) step further.  Is a personal data mart on your desk top as good as a full fledged departmental data mart with an army of highly paid developers maintaining it?  Probably not.

Is the personal data mart on your desk basicly free in comparision to the servers, software and hired help the data mart requires?- Yes. And does it, just like the data mart does for the data warehouse, prepare the ground for the next evolution when the economy turns around? Yes. Yes it does.

In difficult times companies that are pragmatic, and do what is possible, preparing for the day when more will be, survive to see that day.

It seems obvious that doing nothing because you can’t afford to do the best thing is a bad strategy- but we need to ask ourselves, how often do we make that exact choice through inaction?