This is exactly how not to run an open source project if you want it to be a cash cow for a single business but it is how to run an open source project if you want it to reach as large of a user base as possible and provide as many economic opportunities as possible.
PostgreSQL is a community developed, multi-vendor project. Vendors come and go, but the community endures. Many vendors who used to contribute to the project no longer do so but there are a number of mainstays. This article was written in September of 2013, and if you are reading it years later, please be aware there may be additional sources of support available.
Because PostgreSQL is developed by multiple vendors working together, in theory any vendor which employs competent programmers can fix bugs, offer hot fixes, and more for clients, and can, reasonably, if the patches are of good quality, get them accepted upstream. This is an extremely important selling point for the database management system.
There are several long-standing companies in the community which offer support accounts on the database itself. This is on top of vendors like Red Hat who offer high quality support with their OS service level agreements.
This list provided here is largely for journalists and others who wish to discuss PostgreSQL support. It is by no means exhaustive nor is it intended to be. Support is available in various markets through other companies as well and one of our tasks as a community is to create a larger amount of support and consulting services, serving a larger variety of markets. This is a strength of the community development model (as opposed to the vendor development model).
In the interest of full disclosure, I am a principal consultant for 2ndQuadrant, and I have worked with folks from Command Prompt, PGExperts, and some other companies on various projects. Some aspects of what I say here come from something of an insider's perspective.
- 2ndQuadrant offers high quality 24x7 support delivered by support engineers which include actual contributors to the software. Some of their support offerings offer guarantees not found by the vendors of proprietary databases. I say this as a former employee of Microsoft's Product Support Services division.
- Command Prompt. Inc offers service level agreements which ensure quite a bit of proactive assistance. The firm is one of the long-standing mainstays of the PostgreSQL scene.
- PGExperts offers a number of services aimed at ensuring support for critical production environments.
- EnterpriseDB offers support for the official version of PostgreSQL, as well as their own proprietary spinoff, "Postgres Plus Advanced Server." Their proprietary version has a number of features aimed at smoother migration from Oracle, although it is sometimes mistaken for an "enterprise edition" of PostgreSQL.
The companies which I have listed above are largely those where I have met people from them and know something about their business models. The project also maintains list of professional service providers who have opted in to be listed. Note that some service providers may provide technical support or not.
In the end, this model of support is a selling point of the software. Unlike with Oracle, the companies which provide support have to serve the customer's needs because otherwise the customer can go elsewhere.
PostgreSQL is used in a large number of critical production capabilities where the ability to call someone for support, and get a very competent second set of eyes when things go wrong is absolutely necessary, and the companies above provide that. But the companies listed go further, and are able to support the software as if they were the vendor (or likely even better).