ObjectDB Database Search

Jakarta Persistence (JPA) Method in jakarta.persistence.Query Query setHint (    String hintName ,    Object value ) Set a query property or hint. The hints elements may be used ... . Portable applications should not rely on the standard timeout hint. Depending on the database in use

are query identification variables that iterate over all the database objects of a specific entity ... over all the Country objects in the database : SELECT c FROM Country AS c The AS keyword is optional ... is required when using multiple range variables. Iteration over about 1,000,000 database objects

for managed entity objects , including transparent navigation to other database objects , transparent update ... The ability to retrieve managed entity objects is a major advantage of JPQL. For example, the following query returns Country objects that become managed by the EntityManager em : TypedQuery query

the @Transient annotation). Storing an entity object in the database does not store methods or code ... for every entity object . The initial version of a new entity object (when stored in the database ... that do not participate in persistence and their values are never stored in the database (similar

As explained in chapter 2 , entity objects can be deleted from the database by ... the database , but when executed, delete specified entity objects from the database . Removing entity objects from the database using a DELETE query may be slightly more efficient than retrieving entity objects

To be able to store Point objects in the database using JPA we need to define an entity class ... that is marked (annotated) as having the ability to represent objects in the database . Conceptually ... class, and accordingly, provides the ability to store Point objects in the database and retrieve

, which is a Long object reflecting the number of Country objects in the database : TypedQuery query = em ... . In other cases our expectation for a single object result might fail, depending on the database ... . If the database contains multiple Country objects with the name 'Canada' (e.g. due to a bug

. If an entity object is not available also in the shared cache - it is retrieved from the database and added ... Every EntityManager owns a persistence context , which is a collection of all the entity objects ... an entity object that is already managed by the  EntityManager returns the existing instance from

class can only be stored in the database as embedded objects , i.e. as part of a containing entity ... The term persistable types refers to data types that can be used for storing data in the database ... can be stored in the database directly. Other persistable types can be embedded in entity classes as fields

, but when executed, update the content of specified entity objects in the database . Updating entity objects in the database using an UPDATE query may be slightly more efficient than retrieving entity objects ... Existing entity objects can be updated, as explained in chapter 2 , by: Retrieving

clause. When a GROUP BY clause exists in a JPQL query, database objects (or tuples of database objects ... over all the Country objects in the database . The GROUP BY clause groups these Country objects by ... properties of generated groups instead of individual objects and fields. The position of a GROUP BY

to iterate over all the Country objects in the database . For a country with no capital city, such as ... returns the number of all the entity objects in the database , excluding Country entity objects ... are assigned as arguments. Path expressions that navigate from one object to another. Instances of user

rather than just field values from database tables, as with SQL. That makes JPQL more object oriented friendly ... Query The following query retrieves all the Country objects in the database : SELECT c FROM Country ... over objects in the database . A query variable that is bound to an entity class is referred to as a range

). @PostPersist - after storing a new entity in the database (during commit or flush ). @PostLoad - after an entity has been retrieved from the database . @PreUpdate - when an entity is identified as modified by the EntityManager . @PostUpdate - after updating an entity in the database (during commit or flush

The ObjectDB Object Database ObjectDB is a powerful Object -Oriented Database Management ... Features 100% pure Java Object -Oriented Database Management System (ODBMS). No proprietary API ... , JBoss and Spring. See the  ObjectDB Object Database Features  for more details.

JPQL query that retrieves selective objects from the database . Out of the four optional clauses ... over all the Country objects in the database using the c range variable. Before passing these Country ... with millions of objects in the database there is a huge difference in query execution time if proper

associated with a persistence context are considered managed objects , with a well-defined lifecycle ... , that is scheduled for removal from the database upon transaction commit. The EntityManager API is used ... that there is no explicit "update" operation; since an entity is a managed object , modifications

(as classes and objects ). ObjectDB is the only database management system with built in support ... The Java Persistence API (JPA) is a standard API for accessing databases  from within Java applications. The main advantage of JPA over JDBC (the older Java API for interacting with databases

Jakarta Persistence (JPA) Field in jakarta.persistence.PersistenceConfiguration SCHEMAGEN_ DATABASE _ACTION The action to be performed against the database . Standard actions are: none , create , drop , drop-and-create , validate . Since: Jakarta Persistence (JPA) 1.0

in Query and TypedQuery support method chaining (by returning the query object on which they were invoked). Flush Mode (setFlushMode) Changes made to a database using an EntityManager em can be visible ... is executed, uncommitted database changes (if any) have to be flushed to the database in order

ObjectDB is an Object Oriented Database Management System (ODBMS). It provides all the standard database management services (storage and retrieval, transactions, lock management, query processing ... objects (and graphs of objects ) in an ObjectDB database directly. There's no need to define tables

: Exceptions can also be thrown on an attempt to retrieve entity objects from the database . For example ... (above) may also be thrown during retrieval, if database lock has been requested for retrieved entity objects and it cannot be granted. ... JPA exceptions are represented by a hierarchy of unchecked exceptions: java.lang. Object java.lang

with the ObjectDB object database . Given the simplicity of ObjectDB, that should be quick and easy even for a novice. ... ObjectDB databases and perform basic CRUD operations (Create/Store, Retrieve, Update and Delete) on ObjectDB databases . The example program that this chapter presents manages a simple database

number generator for every database . This number generator is used to generate automatic object IDs for entity objects with no primary key fields defined (as explained in the previous section ). The same ... for every new entity object . These generated values are unique at the database level and are never recycled

Jakarta Persistence (JPA) Constructor in jakarta.persistence.LockTimeoutException LockTimeoutException (    Object entity ) Constructs a new LockTimeoutException exception with the specified object . Parameters: entity - the entity. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.EntityManager boolean contains (    Object entity ) Determine if the given object is a managed entity instance belonging to the current persistence context. Parameters: entity - entity instance Returns: boolean value indicating

Jakarta Persistence (JPA) Method in jakarta.persistence.criteria.CriteriaBuilder Predicate equal (    Expression x ,    Object y ) Create a predicate for testing the arguments for equality. Parameters: x - expression y - object Returns: equality predicate. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.criteria.CriteriaBuilder Predicate notEqual (    Expression x ,    Object y ) Create a predicate for testing the arguments for inequality. Parameters: x - expression y - object Returns: inequality predicate. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.Cache void evict (    Class cls ,    Object primaryKey ) Remove the data for the given entity from the cache. Parameters: cls - entity class primaryKey - primary key Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.PersistenceConfiguration PersistenceConfiguration property (    String name ,    Object value ) Set a property of this persistence unit. Parameters: name - the property name value - the property value Returns: this configuration. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.PersistenceUnitUtil boolean isLoaded (    Object entity ) Determine the load state of an entity belonging to the persistence unit. This method can be used to determine the load state of an entity passed as a reference. An entity

Jakarta Persistence (JPA) Method in jakarta.persistence.PersistenceUnitUtil boolean isLoaded (    Object entity ,    String attributeName ) Determine the load state of a given persistent attribute of an entity belonging to the persistence unit. Parameters: attributeName - name

Jakarta Persistence (JPA) Method in jakarta.persistence.TypedQuery TypedQuery setParameter (    String name ,    Object value ) Bind an argument value to a named parameter. Parameters: name - parameter name value - parameter value Returns: the same query instance. Throws

Jakarta Persistence (JPA) Method in jakarta.persistence.TypedQuery TypedQuery setParameter (    int position ,    Object value ) Bind an argument value to a positional parameter. Parameters: position - position value - parameter value Returns: the same query instance. Throws

Jakarta Persistence (JPA) Constructor in jakarta.persistence.OptimisticLockException OptimisticLockException (    Object entity ) Constructs a new OptimisticLockException exception with the specified entity. Parameters: entity - the entity. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.StoredProcedureQuery StoredProcedureQuery setParameter (    int position ,    Object value ) Bind an argument value to a positional parameter. Parameters: position - position value - parameter value Returns: the same query

Jakarta Persistence (JPA) Method in jakarta.persistence.StoredProcedureQuery StoredProcedureQuery setParameter (    String name ,    Object value ) Bind an argument value to a named parameter. Parameters: name - parameter name value - parameter value Returns: the same query

Jakarta Persistence (JPA) Constructor in jakarta.persistence.OptimisticLockException OptimisticLockException (    String message ,    Throwable cause ,    Object entity ) Constructs a new OptimisticLockException exception with the specified detail message, cause

Jakarta Persistence (JPA) Constructor in jakarta.persistence.PessimisticLockException PessimisticLockException (    Object entity ) Constructs a new PessimisticLockException exception with the specified entity. Parameters: entity - the entity. Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Constructor in jakarta.persistence.PessimisticLockException PessimisticLockException (    String message ,    Throwable cause ,    Object entity ) Constructs a new PessimisticLockException exception with the specified detail message, cause

Jakarta Persistence (JPA) Constructor in jakarta.persistence.LockTimeoutException LockTimeoutException (    String message ,    Throwable cause ,    Object entity ) Constructs a new LockTimeoutException exception with the specified detail message, cause, and entity

Jakarta Persistence (JPA) Method in jakarta.persistence.EntityManager LockModeType getLockMode (    Object entity ) Get the current lock mode held by this persistence context on the given managed entity instance. Parameters: entity - a managed entity instance Returns: the lock mode

Jakarta Persistence (JPA) Method in jakarta.persistence.EntityManager void setProperty (    String propertyName ,    Object value ) Set an entity manager property or hint. If a vendor-specific property or hint is not recognized, it is silently ignored. Parameters: propertyName

Jakarta Persistence (JPA) Method in jakarta.persistence.Persistence.PersistenceUtilImpl boolean isLoaded (    Object entity ,    String attributeName ) Since: Jakarta Persistence (JPA) 1.0

Jakarta Persistence (JPA) Method in jakarta.persistence.Persistence.PersistenceUtilImpl boolean isLoaded (    Object entity ) Since: Jakarta Persistence (JPA) 1.0

Operations on the database will be performed by an instance of a Data Access Object (DAO ... - for storing a new  Guest entity object in the database . getAllGuests - for retrieving all the existing  Guest objects from the database . By using Spring components we can move some work from

Operations on the database will be performed by an instance of a Data Access Object (DAO ... - for storing a new  Guest entity object in the database . getAllGuests - for retrieving all the existing  Guest objects from the database . By using Spring components we can move some work from

the next tutorial step) - a new Guest entity object is constructed and stored in the database . All the Guest entity objects are retrieved from the database and stored in the request's "guest" attribute ... , IOException { // Obtain a database connection: EntityManagerFactory emf = (EntityManagerFactory

is constructed and stored in the database . All the Guest entity objects are retrieved from the database ... , HttpServletResponse response) throws ServletException, IOException { // Obtain a database connection ... .getRequestDispatcher("/guest.jsp") .forward(request, response); } finally { // Close the database connection

databases is more important than general portability to both object and relational databases . JPA is designated to be used mainly with relational databases . ObjectDB is the only object database ... databases and it is probably the most popular Java API for object databases today.