For years, developers have been downloading databases — largely open-source — to try out the technology. That work is highly influential, but what is its impact on a business's eventual choice of database?
Bob Wiederhold, CEO of open-source NoSQL database firm Couchbase, thinks the market has now entered a second phase in which deep strategic enterprise evaluations are replacing smaller, predominantly developer-driven trials of the first phase of the technology.
"Grassroots adoption is certainly a fundamental driver for us," Wiederhold said. "Whereas MongoDB, for example, excelled in phase one. They focused on ease of development and that's why they became the most popular NoSQL database and they are today.
"They have far more customers than we do. But now that phase two has kicked in we have a smaller number of very big customers."
a new round of investment worth $60m to help fund further work on its mobile software and the creation of a worldwide technical support channel.
, argues that open-source providers continue to compete "for the eyeballs of the developer" rather than target CTOs or CIOs.
He cited a global bank that told him about the extensive open-source database software downloaded by its developers.
"[They said] developers can download it. They don't have to go through procurement; they don't have to buy hardware. They just download it onto their desktop machine," Bloom said.
"I asked them, 'What do you think about that?' And their response was, 'We can't run our bank on it'. So we compete for mindshare with the open-source providers because they're dominating with this religious open-source argument about how you develop and how you build."
Nevertheless, Bloom agrees that developer-driven demand was and still is highly influential because of the amount of experimentation and education resulting from it.
"What it has helped with is an overall transition. If I look back to when I joined the company a couple of years ago, I had to spend a lot of time with customers explaining to them why they needed another database," he said.
"The last thing most customers in the enterprise want to do is to buy another database or download another database and then run and administer another database.
"What the open-source world has done on a pervasive basis is it has allowed all those people to learn, explore, experiment and get comfortable with the idea of, 'Yes, I actually do need a different technology to solve many of these problems'."
But then enterprises start to consider datacentre production issues, including backup, remote disaster recovery, security and consistency, Bloom said.
"It's been a real education. What this pervasive use by the developers did it has helped educate the market that there's a new way to solve these problems but then ultimately they can't deliver on what's needed in the enterprise," he said.
Dave Page, a member of open-source database project PostgreSQL's core team and EnterpriseDB chief architect, suggests a more balanced picture, with developers and IT management both contributing to the eventual choice of database.
as well as its own managed branch of the PostgreSQL relational database.
"If you ask our sales guys they'll probably say it tends to come from the top down," Page said. "If you ask the people who work in the Postgres community, I suspect they'd say it comes from the bottom up. I think the reality is it's a little of both and it depends on where you're looking at it from."
Page said he has seen changes driven in organisations large and small which have come from both ends of the spectrum.
"I've seen developers who have used Postgres for their hobbies and have recommended it to their bosses and it has become more and more a part of the organisation," he said.
"I've also seen places — for example, large international banks — where it has come down from the CIO. They've got involved and said, 'Yeah, I think we're going to do this', and they've pushed it down."
Page said it may well be the case that the initial impetus from the developer community for certain database technologies is to a certain extent now being supplanted by enterprise-level decision making.
"Postgres has its roots in academia originally, but as PostgreSQL in open source, so certainly it was visible there much earlier than it probably was at the higher levels of enterprises," he said.
Features and cost now play equally important roles in the choice of database, according to Page.
"It's a little of both to be honest," he said. "Obviously, in the open-source community the cost of MySQL was never really a big issue unless you were going to release any software that needed to incorporate any of the MySQL code that was covered by GPL and therefore had to buy a licence from Oracle.
"So for the open-source guys that was not necessarily a problem. In enterprises, people tend to be used to paying Oracle prices anyway or SQL Server prices. There it's perhaps more partly about the prices."