Configuring Automatic Database Table Creation

You can configure OC4J to automatically create (and, optionally, delete) database tables for your persistent objects (see "Using Deployment XML").

You can use this feature in conjunction with default mappings (see "Configuring Default Mappings").

Using Deployment XML

You can configure automatic database table creation at one of three levels as Table 14-2 shows. You can override the system level configuration at the application level and you can override system and application configuration at the EJB module level.

Table 14-2 Configuring Automatic Table Generation

Level	Configuration File	Setting	Values
System (global)	`<OC4J_HOME>/config/application.xml`	`autocreate-tables`	`True`^Foot 1 or `False`
System (global)	`<OC4J_HOME>/config/application.xml`	`autodelete-tables`	`True` or `False`^Footref 1
Application (EAR)	`orion-application.xml`	`autocreate-tables`	`True`^Footref 1 or `False`
Application (EAR)	`orion-application.xml`	`autodelete-tables`	`True` or `False`^Footref 1
EJB Module (JAR)	`orion-ejb-jar.xml`	`pm-properties` sub-element `default-mapping` attribute `db-table-gen`^Foot 2	`Create`, `DropAndCreate`, or `UseExisting`^Foot 3

^Footnote 1Default.

^Footnote 2For more information, see "Configuring default-mapping Properties" on page 8-11.

^Footnote 3See Table 14-3.

If you configure automatic table generation at the EJB module level, the value you assign to the db-table-gen attribute corresponds to the autocreate-tables and autodelete-tables settings as Table 14-3 shows.

Table 14-3 Equivalent Settings for db-table-gen

db-table-gen Setting	autocreate-tables Setting	autodelete-tables Setting
`Create`	`True`	`False`
`DropAndCreate`	`True`	`True`
`UseExisting`	`False`	NA