NPersistence Reference Guide
Defines the values of the NPersistence.lock.scope property for pessimistic locking.

This property may be passed as an argument to the methods of the EntityManager, Query, and TypedQuery interfaces that allow lock modes to be specified or used with the NamedQuery annotation.

Namespace: NPersistence
Assembly: NPersistence (in NPersistence.dll) Version: (


public enum PessimisticLockScope


This value defines the default behavior for pessimistic locking. The persistence provider must lock the database row(s) that correspond to the non-collection-valued persistent state of that instance. If a joined inheritance strategy is used, or if the entity is otherwise mapped to a secondary table, this entails locking the row(s) for the entity instance in the additional table(s). Entity relationships for which the locked entity contains the foreign key will also be locked, but not the state of the referenced entities (unless those entities are explicitly locked). Element collections and relationships for which the entity does not contain the foreign key (such as relationships that are mapped to join tables or unidirectional one-to-many relationships for which the target entity contains the foreign key) will not be locked by default.
In addition to the behavior for PessimisticLockScope.NORMAL, element collections and relationships owned by the entity that are contained in join tables will be locked if the NPersistence.lock.scope property is specified with a value of PessimisticLockScope.EXTENDED. The state of entities referenced by such relationships will not be locked (unless those entities are explicitly locked). Locking such a relationship or element collection generally locks only the rows in the join table or collection table for that relationship or collection. This means that phantoms will be possible.

See Also