{note:This documentation applies to Confluence 2.6}
This documentation applies to Confluence version 2.6.x. The latest Confluence documentation is available via [this link|DOC:].
{note}

{composition-setup:next-free-value=20}
This document provides information on configuring an external database.

h2. Database Selection

Production instances of *Confluence should use an external database*. The default hSQL database has a risk of unrecoverable data loss due to not being [transaction-safe|http://en.wikipedia.org/wiki/ACID].

Corruption is occassionally encountered after sudden power loss and can usually be corrected using [this data recovery procedure|Troubleshooting the Embedded Database (hSQL DB)]. hSQL is still suitable for evaluation purposes, but the risk can only be eliminated by switching databases. External databases may also provide superior speed and scalability. Below is more information on selecting an external database.

* [List Of Supported Databases]
* [Known Issues For Supported Databases]

h2. Database Setup

Setup instructions are shown below; click on a database to review the setup guide and any known issues.

{toggle-cloak:id=1} *MySQL*
{cloak:id=1}{contentbylabel:mysql-setup|showLabels=false|maxResults=99|showSpace=false|key=@self}
{cloak}

{toggle-cloak:id=2} *PostgreSQL*
{cloak:id=2}{contentbylabel:postgresql-setup|showLabels=false|maxResults=99|showSpace=false|key=@self}
{cloak}

{toggle-cloak:id=3} *Oracle*
{cloak:id=3}{contentbylabel:oracle-setup|showLabels=false|maxResults=99|showSpace=false|key=@self}
{cloak}

{toggle-cloak:id=4} *SQL Server*
{cloak:id=4}{contentbylabel:sqlserver-setup|showLabels=false|maxResults=99|showSpace=false|key=@self}
{cloak}

{toggle-cloak:id=5} *DB2*
{cloak:id=5}{contentbylabel:db2-setup|showLabels=false|maxResults=99|showSpace=false|key=@self}
{cloak}

{toggle-cloak:id=6} *Sybase Database*
{cloak:id=6}{contentbylabel:sybase-setup|showLabels=false|maxResults=99|showSpace=false|key=@self}
{cloak}

Other databases should use [Database Setup For Any External Database].

h2. Optimise Database Performance

To improve database responsiveness:
* [Improving Database Performance]
* [Known Issues For Supported Databases]

h2. Database Troubleshooting

For solving database-related problems:
* [Troubleshooting External Database Connections]
* [Troubleshooting the Embedded Database (hSQL DB)]
* [Interpreting DB2 Error Codes]
* [Known Issues For Supported Databases]

Obtain technical support from [Troubleshooting Problems & Requesting Technical Support]