From the number of vendors entering the market as suppliers of data warehouse appliances you would think that this was a major growth area. It probably is. And you would also think it was easy. It isn't.

Here is a list of the companies that, over the last few years, have attempted to move into this market: Netezza, DATAllegro, XPrime, Metapa, Greenplum, Calpont and Vertica. I have heard rumours of one other vendor that is planning to move into the sector as well, but that remains unconfirmed.

Now consider the fate of these vendors and their products:

• Netezza—up and running and growing strongly, proof that there really is a market here.
• DATAllegro—tells a good story and, reputedly, is about to announce its first customers. I know who these are (if I told you I'd have to kill you) but what is worrying is that this announcement seems to have been pending for some time—and the longer the delay the more worrying it becomes. At least the company has a decent source of finance, unlike XPrime.
• XPrime—had problems with its funding and has closed. Core staff members are re-starting with a new venture in the same area.
• Metapa—failed and got merged into Greenplum.
• Greenplum—things have gone ominously silent and there remains a question mark over whether there is really a market for Open Source data warehousing.
• Calpont—concluded that its first generation product would not cut the mustard and has embarked on a second generation offering. I like the potential of this product but we will have to wait and see.
• Vertica—new company set up by Michael Stonebraker with the stated aim of developing a "very fast, highly scalable data warehouse solution". At present still in development but Stonebraker's name bodes well.

What should be pretty obvious from all of this is that Netezza is successful and everybody else is trying to emulate them. What is not clear is whether any of the other vendors will do so. And, if so, who? There is also an apparent question of funding. While VC companies are interested in the market following Netezza's success you have clearly got to have a good story to tell.

How much space is there in the market? Well, three or four vendors maximum probably. And bear in mind that in the UK at least, there is also Kognitio, previously WhiteCross, which more or less fits into this category. But with existing customers and a 20 year history the same criteria do not apply. So, no more than a couple of vendors from the list above, apart from Netezza, are likely to survive. This in itself creates a major problem: organisations will need a lot of persuading before they invest substantial sums in companies that may not be around for long.

While I hope that at least some of the vendors listed survive and prosper, at the moment it looks very much like a one horse race: Netezza is out in front and at present it is leading by a distance. I don't see that changing much any time soon.