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desire to have my persistent objects be cached until the Java Virtual Machine (JVM) does ... Used (LRU) mechanism to get rid of older objects before more recently accessed ones.  I ... for its Level One (L1) object data cache.  I disable the L2 cache and use 1 MB for the ObjectDB

objects is more than you may expect and much slower than just reading the data from the disk. Using embedded objects or report queries (which return fields rather than entity objects) may help. but of course, this may not help if you need all the objects in memory

Every entity object that is stored in the database has a primary key. Once assigned, the primary key cannot be modified. It represents the entity object as long as it exists in the database. As an object database, ObjectDB supports implicit object IDs, so an explicitly defined

, which is a collection of all the entity objects that it manages. The persistence context serves as a first level cache. An attempt to retrieve an entity object that is already managed by the EntityManager ... entity object. The scope of the persistence context is one 

Employee, won't result in this object being available in the same transaction: ie: for (Employee e : department.employee) won't include the new object ... side will be updated automatically when the object is retrieved from the database again.

over objects in the database. A query identification variable is similar to a variable of a Java enhanced for loop in a program, since both are used for iteration over objects. objects of a specific entity class hierarchy (i.e. an entity

specification, are ignored by ObjectDB if specified (as a pure object database, ObjectDB always uses datastore identity with its own object-id class). 4.3  Metadata for Fields ... is java.lang.Object or some interface, but holds at runtime only values of persistent

using JDO. Instances of these classes that represent objects in the database are called persistent objects or persistent instances. Objects that do not represent anything in ... objects or transient instances. The JDO specification refers to persistent classes as

, retrieving, updating and deleting database objects, are provided in the next chapter (objects are accessed through the standard JDO ... object. The strong one to one relationship implies that, theoretically, transaction management

object that failed the consistency check. No datastore resources acquired during the execution ... /java/jpa/EntityManager/contains_Object" title="Method of javax.persistence.EntityManager">contains (Object entity) Check if the instance