From PostgreSQL wiki
This page contains a list of features, for publication for each alpha release.
- DROP COLUMN and DROP CONSTRAINT now support an IF EXISTS clause so that you can avoid errors when running repeatable scripts.
- UNIQUE constraints can now be DEFERRABLE
- GEQO generic algorithm query plans, for very complex queries, can be made repeatable by setting a geqo_seed. This will help with debugging bad plans generated by GEQO.
Stored Procedures / Functions
Administration and Monitoring
- You may now display the SQLSTATE error code as part of the log_line_prefix in your log by using the %e switch.
- pg_standby no longer links to a specific libpq version, preventing unnecessary incompatibility issues.
- pgbench is now multi-threaded, allowing it to use multiple CPU's for its client connections.
- The \d+ describe table shortcut now shows the child tables which inherit from the specified table.
- The \di index describe command now shows the index method.
- We have change the names of some internal functions to remove conflicts with C++ reserved words. This will make it easier to plug-in C++ code to the PostgreSQL codebase.