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All new feature work and bug fixes in Hive are contributed to the master branch. As As of June 2015, releases from master are numbered 2.x. 2.x versions are not necessarily backwards compatible with 1.x versions.
branch-1 is used to build stable, backward compatible releases. Releases Releases from this branch are numbered 1.x (where 1.3 will be the first release from it, as 1.2 was released from master prior to the creation of branch-1). Until Until at least June 2016 all critical bug fixes (crashes, wrong results, security issues) applied to master must also be applied to branch-1. The The decision to port a feature from master to branch-1 is at the discretion of the contributor and committer. However However no features that break backwards compatibility will be accepted on branch-1.
In addition to these main lines Hive has a two types of branches, release branches and feature branches.
Release branches are made from branch-1 (for 1.x) or master (for 2.x) when the community is preparing a Hive release. Release Release branches match the number of the release (e.g., branch-1.2 for Hive 1.2). For For patch releases the branch is made from the existing release branch (to avoid picking up new features from the main line). For For example, if a 1.2.1 release was being made branch-1.2.1 would be made from the tip of branch-1.2. Once Once a release branch has been made, inclusion of additional patches on that branch is at the discretion of the release manager. After After a release has been made from a branch, additional bug fixes can still be applied to that branch in anticipation of the next patch release. Any Any bug fix applied to a release branch must first be applied to master (and branch-1 if applicable).
Feature branches are used to develop new features without destabilizing the rest of Hive. The The intent of a feature branch is that it will be merged back into master once the feature has stabilized.
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This section only gives the basic procedures for attaching and submitting a patch. See See Contributing Your Work below for more information.
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