=== Changing the Database ===

To change the database used by gnuMims a custom WAR must be built from the source code.
 * Perform an anonymous checkout.
 * Change grails-app/conf/DataSource.groovy file to suite.
 * Test or build your custom war with "grails run-app" or "grails war" commands.

Most common databases are supported by Grails (via Hibernate), we test and run MySQL (InnoDB). [[BR]]
The database must support transactions and row locking. [[BR]]
A jar matching the configuration needs to be placed in the projects lib dir (e.g. lib/mysql-connector-java-5.1.7-bin.jar [http://dev.mysql.com/downloads/connector/j/5.1.html Connector]) [[BR]]
See the headings bellow for more details on each database tested so far. [[BR]]

For more info see the DeveloperStartPage and [http://www.grails.org/Quick+Start#Configure%20a%20Data%20Source%20(Optional) Grails documentation].

'''MySQL''

MySQL is the database we use most often and therefore the most thoroughly test and highly recommended. [[BR]]
Also see [wiki:InstallationTips Installation Tips]. [[BR]]

'''PostgreSQL''

Not tested, please email us if you have tested against PostgreSQL. [[BR]]
We will run some tests against PostgreSQL when time permits or if requests are made. [[BR]]

'''MSSQL'''

Live deployment in progress (11-Jan-2010) no issues so far. [[BR]]

'''Oracle DB'''

Currently gnuMims will not run against an Oracle DB without some work. [[BR]]
The known issues should be surmountable and are listed bellow:
 * 30 Char limit:
  * Several gnuMims domain classes and attributes exceed this limit  .
  * This is possibly the biggest issue since Grails will create join tables for classes '!MyDomainClassName1' and '!MyDomainClassName2' as 'my_domain_class_name1_my_domain_class_name2'.
  * Table mappings may be of use here?
  * Abbreviated names would make building reports directly from the database much less intuitive.
 * The default sequence generator does not create Id's as expected, a suitable hibernate sequence generator needs to be set.
 * To store empty strings the IS_NULLABLE metadata for the column needs to be set.
 * [http://www.stanford.edu/dept/itss/docs/oracle/9i/server.920/a96540/ap_keywd.htm Oracle reserved words] ("comment" and "date") this can be solved with a mapping in the appropriate domain classes:
 {{{
    static mapping = {
    columns {
        comment column:'entry_comment'
      }
    }
 }}}