Berkus: Changing PostgreSQL Version Numbering

On his blog, Josh Berkus asks about the effects of changing how PostgreSQL numbers its releases. There is talk of moving from an x.y.z scheme to an x.y scheme, where x would increase every year to try to reduce "the need to explain to users that 9.5 to 9.6 is really a major version upgrade requiring downtime". He is wondering what impacts that will have on users, tools, scripts, packaging, and so on."The problem is the first number, in that we have no clear criteria when to advance it. Historically, we've advanced it because of major milestones in feature development: crash-proofing for 7.0, Windows port for 8.0, and in-core replication for 9.0. However, as PostgreSQL's feature set matures, it has become less and less clear on what milestones would be considered "first digit" releases. The result is arguments about version numbering on the mailing lists every year which waste time and irritate developers."