Specifying the Database

The Enterprise Server uses the bundled Java DB (Derby) database by default. If the transaction-type element is omitted or specified as JTA and both the jta-data-source and non-jta-data-source elements are omitted in the persistence.xml file, Java DB is used as a JTA data source. If transaction-type is specified as RESOURCE_LOCAL and both jta-data-source and non-jta-data-source are omitted, Java DB is used as a non-JTA data source.

To use a non-default database, either specify a value for the jta-data-source element, or set the transaction-type element to RESOURCE_LOCAL and specify a value for the non-jta-data-source element.

If you are using the default persistence provider, the provider attempts to automatically detect the database type based on the connection metadata. This database type is used to issue SQL statements specific to the detected database type's dialect. You can specify the optional eclipselink.target-database property to guarantee that the database type is correct. For example:

<?xml version="1.0" encoding="UTF-8"?>
    <persistence xmlns="http://java.sun.com/xml/ns/persistence">
        <persistence-unit name ="em1">
            <jta-data-source>jdbc/MyDB2DB</jta-data-source>
            <properties>
                <property name="eclipselink.target-database" 
                    value="DB2"/>
            </properties>
        </persistence-unit>
    </persistence>

The following eclipselink.target-database property values are allowed. Supported platforms have been tested with the Enterprise Server and are found to be Java EE compatible.

//Supported platforms
JavaDB
Derby
Oracle
MySQL4
//Others available
SQLServer
DB2
Sybase
PostgreSQL
Informix
TimesTen
Attunity
HSQL
SQLAnyWhere
DBase
DB2Mainframe
Cloudscape
PointBase

For more information about the eclipselink.target-database property, see Using EclipseLink JPA Extensions for Session, Target Database and Target Application Server.

To use the Java Persistence API outside the EJB container (in Java SE mode), do not specify the jta-data-source or non-jta-data-source elements. Instead, specify the provider element and any additional properties required by the JDBC driver or the database. For example:

<?xml version="1.0" encoding="UTF-8"?>
    <persistence xmlns="http://java.sun.com/xml/ns/persistence" version="1.0">
        <persistence-unit name ="em2">
            <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
            <class>ejb3.war.servlet.JpaBean</class>
            <properties>
                <property name="eclipselink.target-database" 
                    value="Derby"/>
                <!-- JDBC connection properties -->
                <property name="eclipselink.jdbc.driver" value="org.apache.derby.jdbc.ClientDriver"/>
                <property name="eclipselink.jdbc.url" 
value="jdbc:derby://localhost:1527/testdb;retrieveMessagesFromServerOnGetMessage=true;create=true;"/>
                <property name="eclipselink.jdbc.user" value="APP"/>
                <property name="eclipselink.jdbc.password" value="APP"/>
            </properties>
        </persistence-unit>
    </persistence>

For more information about eclipselink properties, see Additional Database Properties.

For a list of the JDBC drivers currently supported by the Enterprise Server, see the Sun GlassFish Enterprise Server v3 Release Notes. For configurations of supported and other drivers, see Configuration Specifics for JDBC Drivers in Sun GlassFish Enterprise Server v3 Administration Guide.

To change the persistence provider, see Changing the Persistence Provider.