Using Oracle
When using JPA, you have the option to use the Oracle database.
This option is only supported with Oracle 12c and upwards.
As Oracle is a proprietary database, we cannot give it the same level of support that we do for our other options:
- Its driver is proprietary, so we cannot bundle it with JHipster
- We cannot give it the same level of test, as it is not available on Mac OS X (the final JHipster builds and tests are made on a Macbook Pro)
When using Oracle with JHipster, you will need to install the Oracle JDBC driver manually:
- Download the driver (ojdbc7.jar for Java 8) from the Oracle website
- Copy it to your application’s
lib/oracle/ojdbc/7/folder - You will need to rename your driver, from
ojdbc7.jartoojdbc-7.jar, in order to follow Maven’s naming conventions.
When using Oracle with JHipster, the following limitations will be applicable
- Entity names cannot be more than 26 characters, this is due to Oracle’s 30 character limitation for object names, and we reserve 4 characters to generate primary key sequence for the generated tables.
- Entity field names cannot be more than 30 characters
- When doing relationships, foreign key names cannot be more than 30 characters, so they will be truncated if they are too long
- When doing many-to-many relationships, the join table name will follow the JPA specification (in the form “firstTable_secondTable”): if it is more than 30 characters long, it will be truncated.
- Oracle reserved keywords cannot be used as Entity names or Field names.