About retrieve

manual

WHERE clause (JPQL / Criteria API)

Explains how to use the WHERE clause in a JPQL query. The WHERE clause adds filtering capabilities to the FROM-SELECT structure. It is essential in any JPQL query that retrieves selective objects from the database. Out of the four optional clauses of JPQL queries, the WHERE clause is definitely the most ...

 
forum_thread

OptimisticLockException

Have read read the documentation on optimistic locks, still not sure how to deal with these exceptions: [ObjectDB 2.2.5_04] javax.persistence.RollbackException Failed to commit transaction: Optimistic lock failed for object   #1 2011-05-28 22:27 Have read read the documentation on optimistic locks, still not sure how to deal with these exceptions: [ ...

 
forum_thread

Activation Issue

Hi! We now reached the 10 class limit of ObjectDB. Our license is activated and if I run objectdb activation I get true back. When I start our webapp although I get the following error: #1 2014-10-22 13:07 Hi! We now reached the 10 class limit of ObjectDB. Our license is activated and if I run objectdb activat ...

 
doc

java.lang.Throwable

The Throwable class is the superclass of all errors and exceptions in the Java language.(Class of java.langClass Throwable)

 
manual

JPA Query Structure (JPQL / Criteria)

Explains the structure of a JPQL query, which consists of 6 clauses: SELECT, FROM, WHERE, GROUP BY, HAVING, ORDER BY.... Java classes and objects. For example, a JPQL query can retrieve and return entity objects rather than just field values from database ...

 
api-jpa

JPA Exceptions

Reference (JavaDoc) of the JPA exception classes, including PersistenceException, EntityExistsException, EntityNotFoundException, LockTimeoutException, NonUniqueResultException, NoResultException, OptimisticLockException, PessimisticLockException, QueryTimeoutException, RollbackException, TransactionRequiredException.... Exceptions can also be thrown on an attempt to retrieve entity objects from the database. For example, when a required entity ...

 
manual

Logical Operators in JPQL and Criteria API

Explains how to use AND, OR and NOT in JPQL queries. Logical operators in JPQL and in JPA criteria queries enable composition of complex JPQL boolean expressions out of simple JPQL boolean expressions. This page covers the following topics: Logical Operators ...

 
forum_thread

Project runs in Eclipse but not when exported to runnable jar

I have a simple project that performs some stability calculations and displays a scale drawing of a model glider. I decided to use objectdb as a way to persist the values for later retrieval. The project works perfectly well when run from eclipse but nothing opens when I export to a runnable jar and execute that. No windows open, there are no eror dialogs etc. Commenting out all the code related to object db resolves the issue and the project runs, so I'm fairly sure it is something I've done relating to objectdb. ... basics before working out how to effeciently commit and retrieve the main data. I'm very new to Java, this is the first project ...

 
tutorial

Step 3: Add a Main Class

Explains how to add the JPA tutorial Main class in NetBeans.... order to store Point objects in the database and then retrieve them from the database. Use copy and paste to replace the ... ( ) ) ;   // Retrieve all the Point objects from the database: ...

 
release

2.3.7

Release date: 2012-02-06 Download (5.38 MB) Binary:  objectdb-2.3.7.zip You should start by following a  tutorial or reading the manual ...