Edgewall Software

Version 52 (modified by Ryan J Ollos, 3 years ago) ( diff )

Recomendation on database conversion. SqLiteToMySql page will eventually be deleted.

Database Backend

Trac offers an easily extensible layer for database support, see trac.db.api. The following databases have been integrated in this layer:

There is work in progress for the following databases:

Database Installation Instructions

SQLite

Installed out-of-the-box, provided you have installed the PySqlite bindings.

The following parameters are supported:

  • extensions: Load the extensions, see also TracIni.
  • timeout: Set timeout to connect the database, 10.0 is used by default.
  • cursor: eager cursor pre-fetching all the rows is used by default. It can be turned off by specifying cursor= (#3446).
  • journal_mode: Set the journal mode to the database (since 1.0.5).
  • synchronous: Set the synchronous flag (since 1.0.5).

Known issues: see pysqlite-related tickets.

Postgresql

Prerequisites:

  • Have a working copy of Postgresql.
  • Get the proper database driver for Python, see above.
  • Create a database for your Trac environment:
    % createdb dbname
    
  • Run trac-admin to create a new Trac environment. When prompted for a Database connection string, use:
    postgres://user:pass@localhost:5432/dbname?schema=schemaname
    

Notice that the port number might be different in your Postgresql installation, eg 5433. See postgresql.conf.

Alternatively on UNIX, if the database is a local one, you can use UNIX sockets instead of TCP/IP:

postgres://user:pass@/dbname?host=/path/to/unix/socket/dir&schema=schemaname

If you are using user Trac without a password to connect through UNIX sockets to database trac and have only one project (hence no need for different schemas), your connections string would be postgres://trac:@/trac

  • Note: '?host=…' is optional. Check your postgresql.conf' unix_socket_directory option if you have connection problems.

See #4546 for more details.

See also #2441, which discusses the process of migration from SQLite to Postgresql.

For a Postgresql recipe tested on CentOS4 (Red Hat -EL4) see PostgresqlRecipe.

Note: Since Trac 0.10 the psycopg1 Postgresql driver is no longer supported due to lack of Unicode support.

Known issues: see postgres-related tickets

MySQL

MySQL is supported by Trac since 0.10, but there are some caveats, documented in more details in the MySqlDb page.

  • Run trac-admin to create a new Trac environment. When prompted for a database connection string, use:
    mysql://dbuser:dbpass@host:port/dbname
    
  • or when you need more options:
    mysql://dbuser[:dbpass]@host[:port]/dbname[?param1=value&param2=value]
    

The following parameters are supported since Trac 1.0:

  • compress: Enable compression (0 or 1)
  • init_command: Command to run once the connection is created
  • named_pipe: Use a named pipe to connect on Windows (0 or 1)
  • read_default_file: Read default client values from the given file (also used for SSL configuration)
  • read_default_group: Configuration group to use from the default file
  • unix_socket: Use a Unix socket at the given path to connect

Known issues: see mysql-related tickets.

Database Conversion

TracMigratePlugin allows an environment to be easily migrated between the supported database backends.

Alternative Ideas for Database Independence

Object-Relational Mapper

An ORM could be used to provide a unified object interface to different RDBMS:

  • Modeling, which is another, more advanced OR-Mapper.
  • ADODB, the fast database abstraction layer with a version available for Python.
  • SQLAlchemy is also quite advanced.
  • Some people have been talking about using SQLObject to accomplish this goal of database independence.

Store Tickets and Wiki pages directly in the Subversion repository

A compelling idea with many advantages. A page advocating this plan is TighterSubversionIntegration. There has also been a discussion on the Trac mailing list, of which the arguments are summarized on the page WhySQLite.


See also: SqlAlchemy

Note: See TracWiki for help on using the wiki.