Feature Set

The tables below shows the currently supported features for DB4O.

General
Feature Supported
Datastore Identity Yes
Application Identity Yes
Nondurable Identity No
Compound Identity Yes
Pessimistic Transactions Yes
Optimistic Transactions Yes
Surrogate version Yes
Value Generation Yes - native, sequence, uuid-string, uuid-hex, auid, timestamp, timestamp-value
ORM
Feature Supported
Indexes Yes
Unique Keys Yes
Foreign Keys No
Primary Keys No
Inheritance No. Not applicable to OODBMS
Secondary Table No
Embedded PC No
Embedded Collection No
Embedded Map No
Serialised PC No
Serialised Collection No
1-1 Yes
1-N Yes
M-N Yes
Types
Feature Supported
java.lang.Object Yes
java.util.Collection Yes
java.util.Map Yes
Arrays Yes
Interfaces Yes
Queries
Feature Supported
JDOQL Yes, some is evaluated in the datastore, and remainder is evaluated in-memory
JPQL Yes, some is evaluated in the datastore, and remainder is evaluated in-memory