adds a constraint to this node.
[Visual Basic] Function constrain( _ ByVal constraint As Object _ ) As Constraint [C#] Constraint constrain( object constraint ); [C++] Constraint* constrain( Object* constraint ); [JScript] function constrain( Object constraint ): Constraint;
com.db4o.query.Constraint a new com.db4o.query.Constraint for this query node or
nullfor objects implementing the com.db4o.query.Evaluation interface.
adds a constraint to this node.
If the constraint contains attributes that are not yet present in the query graph, the query graph is extended accordingly.
Special behaviour for:
Query Interface | com.db4o.query Namespace