The latest generation of the open source PostgreSQL database is now available with version 9.0 adding support for new replication and failover capabilities, which its developers hope will accelerate adoption in cloud environments.
PostgreSQL 9.0 succeeds the last major release, version 8.4, and brings new features in security, application support, monitoring, performance and data storage.
Upgrades to 9.0 can be made “in-place” from versions 8.3 and 8.4.
For improved replication, PostgreSQL adds hot standby and streaming replication functionality.
Other performance and advanced features include improved event messaging, 64-bit Windows support, expanded support for key-value data and support for Python 3.
Brendan Jurd, a contract developer with Canberra-based accounting firm Achieve Corporation, said PostgreSQL 9.0 will streamline disaster recovery.
“We do backups with periodic database dumps and we are shipping them offsite, but when we have access to streaming replication we will be able to update a slave so if the master went down the slave will be nearly up to date,” Jurd said, adding the transfer would be “within seconds”.
Achieve has an in-house CRM system based on PostgreSQL that Jurd developed and a document store which saves faxes and scans as image files in a database.
“Hot standby means the slave can accept read-only queries so we will probably use that in our backup solution,” he said. “We can make sure the data is up to date so we will use it for DR.”
Jurd said in-place upgrade support will make things “go a little faster” when PostgreSQL is upgraded.
“We can take the system down as it’s not a 24-by-7 operation, but for those that need it, upgrades can be time consuming. For us an offline upgrade it takes about an hour,” he said.
Achieve has six instances of PostgreSQL running and used Ubuntu Linux servers in production and Gentoo Linux for development.
PostgreSQL is an open source project with a distributed contributor base, including commercial supporters like NTT Open Source, EnterpriseDB, 2ndQuadrant, Red Hat and the EMC-owned Greenplum.
Database service provider 2ndQuadrant was the lead contributor to hot standby support for 9.0.
CTO Simon Riggs said built-in replication and ability to query a hot standby have been the most requested PostgreSQL features for many years.
"In proprietary products, this capability is an add-on which costs thousands of dollars," Riggs said.
Global top-level domain name registry and DNS provider Afilias manages 16 million domains with PostgreSQL.
Afilias CTO Ram Mohan said in-place upgrades in version 9.0 will allow upgrades to new versions of the database system with minimal disruption.
Another mission-critical enterprise PostgreSQL user is the CAIXA Bank in Brazil.
The bank’s IT vice president Clarice Coppetti said PostgreSQL is used in financial environments because “it has the quality to support our operations”.