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api-jpa

javax.persistence.CascadeType

Defines the set of cascadable operations that are propagated to the associated entity.(Enum of JPA)

 
api-jpa

parameter(paramClass)

Create a parameter expression.(Method of javax.persistence.criteria.CriteriaBuilder)

 
forum_thread

Cache usage

after a runtime of several weeks we are now analyzing the usage of the cache and so on. Looking at the heap dump we suspect that the cache is really used (see heap dump attached), the RAM allocated by objectdb is much less than we would expect. The database file has around 25 GByte of size and there is heavy traffic of around 400 clients communicating permanently via webSockets to the objectdb. The config is attached as well. The question is: is the cache really used ? ... heap dump shows usage of several ObjectDB caches: Page Cache (processing cache="2048mb") It seems that when the heap dump was taken the size of the database page cache was about 1.4GB. It is less than the 2GB specified in the ...

 
api-jpa

CascadeType.ALL

Cascade all operations(Enum Constant of javax.persistence.CascadeType)

 
api-jpa

find(entityClass, primaryKey)

Find by primary key.(Method of javax.persistence.EntityManager)

 
api-jpa

javax.persistence.criteria.Root

A root type in the from clause.(Interface of JPA)

 
api-jpa

persist(entity)

Make an instance managed and persistent.(Method of javax.persistence.EntityManager)

 
api-jpa

createQuery(qlString, resultClass)

Create an instance of TypedQuery for executing a Java Persistence query language statement.(Method of javax.persistence.EntityManager)

 
api-jpa

javax.persistence.criteria.CriteriaQuery

The CriteriaQuery interface defines functionality that is specific to top-level queries.(Interface of JPA)

 
api-jpa

CascadeType.PERSIST

Cascade persist operation(Enum Constant of javax.persistence.CascadeType)