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Manual
11

JPA Lifecycle Events

(added to the EntityManager). @PostPersist - after storing a new entity in the database (during commit or ... the database (during commit or flush). @PreRemove - when an entity is marked for removal in the EntityManager. @PostRemove - after deleting an entity from the database (during commit or flush). An entity
Manual
10

Index Definition

. A PersistenceException is thrown on commit (or flush) if different entities have the same value in a unique ... with no unique constraint or a unique index if unique="true" is specified (the default is false). The optional ... . When an entity object is stored in the database every indexed field must contain either null or
Manual
10

JPA Metamodel API

Metamodel API is Metamodel. It can be obtained either by the EntityManagerFactory's getMetamodel method or ... instance: // Get a managed type (entity, embeddable or mapped super classes): ManagedType ... class when using multiple ID fields or properties. Finally, the EntityType interface adds
Manual
10

Locking in JPA

that has to be updated or deleted is checked. An exception is thrown if it is found out that an update ... field. During commit (and flush), ObjectDB checks every database object that has to be updated or ... some ORM JPA providers) is defined in the entity class or not. Pessimistic Locking The main
Manual
10

GROUP BY and HAVING clauses

clause. When a GROUP BY clause exists in a JPQL query, database objects (or tuples of database objects ... (count, sum, avg, max, min) that are carried out on all the objects (or the object tuples) in the group ... which all the FROM/WHERE objects (or object tuples) are considered as one group. For example
Manual
10

Paths and Types in JPQL and Criteria API

with an instance of a user defined class (represented by a variable, parameter or prefix path expression ... must contain a persistent field (or property) with a matching name. The path expression ... , a NullPointerException is thrown on any attempt to access a field or a method via a null reference. In
Manual
10

Retrieving JPA Entity Objects

with data that is retrieved from the database (or from the L2 cache - if enabled). The new entity object ... FetchType.LAZY in either @OneToOne or @ManyToOne annotations (currently ObjectDB does not distinguish ... @OneToMany or @ManyToMany annotations (currently ObjectDB does not distinguish between the two) enables
Manual
10

Storing JPA Entity Objects

or implicitly as a result of a cascade operation. Explicit Persist The following code stores ... managed by the EntityManager) or by commit. Referenced Embedded Objects The following code stores ... of every reachable object or alternatively by setting automatic cascading persist. Cascading Persist Marking
Result
10

Posting to ObjectDB Website - Important Instructions

ticket or as an issue. The exceptions are: Clear ObjectDB bugs, such as unexpected exception thrown ... to modify, delete or move any post at its sole discretion. 2. Content and Readability To keep your post ... To demonstrate a technical question or an issue - you may have to provide a complete runnable sample
Manual
9

Query Parameters in JPA

of :name itself is String. Queries can include multiple parameters and each parameter can have one or ... (as other query elements) are represented by objects (of type ParameterExpression or its super interface Parameter) rather than by names or numbers. See the Parameters in Criteria Queries section