17 | IN expression in a Criteria Query: SELECT a FROM Account a GROUP BY a.code HAVING COUNT(a) < 2 It throws following exception: com ... the criteria query into a string with toString). Regarding the GROUP BY query: SELECT a FROM Account a GROUP BY a.code HAVING COUNT(a) < 2 This is an invalid query. In a grouping query |
15 | JDO sequences from ORM file> <!-- Persistable Types with Fetch Groups --> <class name="JdoTypes$ClassWithFetchGroup"> <fetch-group name="fg1" post-load="false"> <fetch-group name="sg1" /> <field name="p" recursion-depth="7" /> </fetch-group> </class> <class name="JdoTypes$ClassWithFetchGroups |
3 | Detached Entity ObjectsDetached entity objects are objects in a special state in which they are not managed by any ... ). Retrieval by navigation from detached objects is not supported, so only persistent fields ... EntityManager. In addition, in JPA 2 we can detach an entity object by using the detach method: em.detach |
3 | Unexpected exception (Error 990) on find error: [ObjectDB 2.4.7_16] Unexpected exception (Error 990) Generated by Java HotSpot(TM) 64-Bit ... -------------------------- Group #1: Page#70606 3:'Elementarprodukt:400000100317025:7:1:' 1/2 1980+609/2589 Group #2: Page#138243 3:'Elementarprodukt:400000100417179:5:1:' 1/2 1980+396/2376 Group #3: Page#165140 3 |
3 | Shared (L2) Entity Cache an entity object that is already managed by the EntityManager returns the existing instance from ... by the EntityManagerFactory and shared by all its EntityManager objects. the broader scope ... is wider, since they exist per database and are shared by all the EntityManagerFactory and EntityManager |
3 | Database Connection using JPA A connection to a database is represented by an EntityManager instance, which also provides ... . An EntityManagerFactory is constructed for a specific database, and by managing resources efficiently (e.g ... the content of a database require active transactions. Transactions are managed by an EntityTransaction |
3 | Index DefinitionQuerying without indexes requires iteration over entity objects in the database one by ... A composite index is an index on more than one persistent field. It is defined by specifying multiple fields ... ; : } Notice that the paths include a collection, so multiple values will be maintained by the index |
2 | JPA Lifecycle Events and are invoked automatically by JPA when these events occur. Internal Callback Methods Internal callback ... - when an entity is identified as modified by the EntityManager. @PostUpdate - after updating an entity in ... events by marking it with more than one annotation. By default, a callback method in a super entity |
0 | javax.jdo.annotations.FetchGroupsjavax.jdo.annotations Annotation FetchGroups Target: Classes Annotation for a group of fetch-group objects Since: JDO 2.1 FetchGroup[] value The Fetch Groups The Fetch Groups Returns: The Fetch Groups Since: JDO 2.1 |
0 | [ODB1] Chapter 2 - A Quick Tour by step. Both sample programs are contained in ObjectDB's samples directory. 2.1 Hello World ... ArrayList list; 18 try { 19 // Retrieve the list from the database by ... is expected to be retrieved from the database by its name "Hello World" using the getObjectById |
