About JOIN

issue

Eager Fetch of Map with Entities as Keys

Loading eagerly a map that uses entity objects as keys is currently unsupported, if the equals and hashCode method of the keys are based on the key entity content, since it is unavailable during instantiation of the map. The following test case demonstrates the problem: Bug Version: 2.3.4 Priority: Normal Status: Active Replies: 0 Type:  Bug ...

 
forum_thread

Database crash

just running objectdb we run into a crash situation as described in the attached log. What can be the reason for such a behaviour ?   #1 2017-07-14 06:40 just running objectdb we run into a crash situation as described in the attached log. What can be the reason for ...

 
forum_thread

How to Use a SF with extended Persistence Context?

Hey, I have a problem to use SF with an Extended Persistence Context Regarding to Transactions. The need for an extended persistence Context emerges for the need to create queries in advance for fast execution so I need to store the queries and I need an EntityManager that doesn't get closed between calls. When I call the SF directly no problem happens but if I use SL to hold a reference to the SF I get com.objectdb.o._PersistenceException: Attempt to begin a new transaction when a transaction is active. #1 2013-11-24 06:05 Hey, I have a problem to use SF with an Extended Persistence Context Regarding to Transactions. T ...

 
manual

Online Backup

Online Backup enables backing up an ObjectDB database while it is in active use by applications. The ability to create a backup while the system is running is essential in applications and services that have to be available 24/7/365.... ( ) ; backupThread. join ( ) ; // Wait until the backup is completed. ...

 
manual

DELETE Queries in JPA/JPQL

Explains how to apply server side bulk delete using a JPA/JPQL query.... DELETE queries cannot include multiple variables and JOIN, and cannot include the GROUP BY, HAVING and ORDER BY clauses. A ...

 
api-jpa

JPA Queries

Reference (JavaDoc) of all the JPA query types, including Query, TypedQuery, CriteriaBuilder, CriteriaQuery, Tuple, Root, Expression, Order, etc.... FROM clause elements (representing range variables, join and fetch): Criteria Query From Elements ...

 
manual

SELECT clause (JPQL / Criteria API)

Explains how to use the SELECT clause and projections in a JPA/JPQL query.... content can be added to the SELECT clause by using a bound JOIN variable in the FROM clause. Nested path expressions are also ...

 
manual

UPDATE SET Queries in JPA/JPQL

Explains how to apply server side bulk update using a JPA/JPQL query.... variable name) for iteration. Multiple variables and JOIN are not supported. The SET clause defines one or more field update ...

 
issue

InternalException when querying indexed field using a list that contains duplicates

ObjectDB is throwing an InternalException in JdoQuery: Bug Version: 1.04 Priority: Normal Status: Active Replies: 0 Type:  Bug ...