Linux, Apache, JBoss, and other open source technologies are kicking sand in the faces of the big boys on the operating system and middleware tiers, but when it comes to the database world, open source is still a 97-pound weakling. And despite some heady growth numbers, that's not likely to change anytime soon.

One big reason: Tool vendors have yet to catch up. "We advise clients that unless they have very strong IT resources, they should wait at least two years to think about deploying an open source database for mission-critical applications," says Colleen Graham, Gartner's longtime database market analyst.

Don't take Graham's words as a put-down of the products. They're not. But Ingres, MySQL, and EnterpriseDB are victims of a classic chicken-and-egg phenomenon. Tool vendors, unlike the database developers, tend to work on a commercial model, and until they see open source winning more database market share, they don't have the incentive to supply the software and enterprise needs for disaster recovery and other essential functions.

Even fast growth won't easily overcome the tiny installed base

As a result, open source database penetration is very low; Gartner estimates that it has a market share of about 1 per cent. Sure, it's growing rapidly, but even after an annual growth of 43 per cent a year for the next four years, it will still have a share of only 5 per cent or so, says Graham.

Consider Ingres, which spun out of CA in 2005. Revenue doubled in 2007, but even so, the top line was a paltry US$50 million. MySQL, purchased by Sun this year for a heady US$1 billion, recorded revenue of just US$48 million in 2007, according to analysts at the 451 Group.

Fred Gallagher, vice president of business development at Ingres, says his company is making progress winning customers for mission-critical applications, and points to DatAllegro, which embeds Ingres in its data warehousing appliance.

Larger companies simply aren't biting

A recent joint survey by the 451 Group and ChangeWave Research shows a good deal of resistance by executives responsible for database procurement. It found that just 8 per cent of all respondents are planning a moderate or significant increase in open source database adoption.

But you can't blame any cooling of the open source phenomenon for the weak traction of open source databases. Open source on the operating system, for example, sees continued gains: Linux was the No. 3 relational database OS with 15.5 per cent market share in 2006, when it grew by 67 per cent over the previous year, Gartner found. (Stats for 2007 won't be ready for another few months.)

It also would be tempting to blame the anemic numbers on the faltering economy, but 41 per cent of those polled (and remember that these are procurement executives) expect to increase spending on proprietary database deployments.

It's also clear that adoption of open source databases is wide but mighty shallow. "A look at the typical workload deployments for open source databases confirms this. Open source databases are most likely to be used for small database applications, and 34 per cent of respondents stated that their largest open source database stored less than 50GB of data," the analysts wrote.