* Fix btree index corruption from insertions concurrent with vacuuming
* Recover from errors occurring during WAL replay of DROP TABLESPACE
* Fix transient zeroing of shared buffers during WAL replay
* Fix postmaster to attempt restart after a hot-standby crash
* Fix corner case in SSI transaction cleanup
* Update per-column permissions, not only per-table permissions, when changing
table owner
* Fix handling of data-modifying WITH subplans in READ COMMITTED rechecking
* Fix for "could not find plan for CTE" failures
* Fix unsupported node type error caused by COLLATE in an INSERT expression
* Avoid crashing when we have problems deleting table files post-commit
* Fix recently-introduced memory leak in processing of inet/cidr
* Fix GIN cost estimation to handle column IN (...) index conditions
* Fix I/O-conversion-related memory leaks in plpgsql
* Teach pg_upgrade to handle renaming of plpython's shared library (affecting
upgrades to 9.1)
* Fix bugs in information_schema.referential_constraints view
* Correct collations for citext columns and indexes
* Prevent possible crash when joining to a scalar function
* Prevent transitory data corruption of GIN indexes after a crash
* Prevent data corruption on TOAST columns when copying data
* Fix failures during hot standby startup
* Correct another "variable not found in subplan target list" bug
* Fix bug with sorting on aggregate expressions in windowing functions
* Multiple bug fixes for pg_upgrade
* Change Foreign Key creation order to better support self-referential keys
* Multiple bug fixes to CREATE EXTENSION
* Ensure that function return type and data returned from PL/perl agree
* Ensure that PL/perl strings are always UTF-8
* Assorted bug fixes for various Extensions
* Updates to the time zone database, particularly to CST6
* Make pg_options_to_table return NULL for an option with no value
* Fix memory leak at end of a GiST index scan
* Fix explicit reference to pg_temp schema in "CREATE TEMPORARY TABLE"
years, removing roadblocks to deploying new or ported applications on
PostgreSQL. These include:
* Synchronous Replication: enable high-availability with consistency across
multiple servers
* Per-Column Collations: support linguistically-correct sorting per database,
table or column.
* Unlogged Tables: greatly improves performance for ephemeral data
Our community of contributors innovates with cutting-edge features. Version 9.1
includes several which are new to the database industry, such as:
* K-Nearest-Neighbor Indexing: index on "distance" for faster location and text
search queries
* Serializable Snapshot Isolation: keeps concurrent transactions consistent
without blocking, using "true serializability"
* Writeable Common Table Expressions: execute complex multi-stage data updates
in a single query
* Security-Enhanced Postgres: deploy military-grade security and Mandatory
Access Control
