PostgreSQL Agenda 2010
2010 will see PostgreSQL release its first major new version for a long time: version 9.0. The release of version 9.0 is an important milestone in the evolution of PostgreSQL. Integral to this release are new features such as the operation of standby servers in read-only mode (hot standby) and an integrated replication solution.
Hot standby will allow a PostgreSQL instance to receive read requests on so-called standby nodes. The basic principle is the same as that included since version 8.0 under the name PITR (Point In Time Recovery) or WAL-Shipping. At regular intervals a copy of the database complete with transaction logs is generated (known as the Write Ahead Log or WAL), so that the standby nodes can be kept up to date with changes in the master database. In practice, this means incrementally applying all changes that were made on the master database from the point when the standby node was created.