The third alpha release for PostgreSQL version 9.1, 9.1alpha3, is now available. This alpha release contains several new major features added since the alpha2 release. Please download, install, and test it to give us early feedback on the features being developed for the future versions of PostgreSQL.
Features added in 9.1alpha3 since alpha2 include:
* KNN GiST, which implements order-by-operator support for GiST and optimizes nearest-neighbor geographic searches. This will power the next release of PostGIS.
* Additional instrumentation and monitoring facilities, including checkpoint introspection and last-WAL-timestamp information for replication.
* Several new built-in functions: format(), pg_describe_object(), as well as pg_read_binary_file(), which will support the Extensions feature.
* New libpq functions: PQping(), PQlibVersion()
* The capability to produce crash dumps on Windows
* New auth_delay module to introduce a delay on failed authentications and make dictionary attacks more difficult.
* Security hooks on object creation, to support SEPostgres.
More detail is available in the release notes: http://developer.postgresql.org/pgdocs/postgres/release-9-1-alpha.html
These new features mean that we need you to participate in testing them. If you are able to help with organized alpha testing, please see the Alpha/Beta testing page: http://wiki.postgresql.org/wiki/HowToBetaTest
Alpha releases are not stable and should never be used in production; they are for testing new features only. There is no guarantee that any features or APIs present in the alphas will be present, or the same, in the final release.
Alpha release information page: http://www.postgresql.org/developer/alpha
Download the alpha release here: http://www.postgresql.org/ftp/source/v9.1alpha3/
Alpha releases are primarily made in source code form only. Binary packages for some operating systems will be prepared in the coming days.