About optimistic

forum_thread

Pessimistic lock

Dear Sir or Madam, In the past we used the default Options in the JDO 1.0. See below for reference: javax.jdo.option.Optimistic=false javax.jdo.option.NontransactionalRead=true javax.jdo.option.NontransactionalWrite=false javax.jdo.option.RetainValues=true javax.jdo.option.RestoreValues=false Now we use the following options in DB2: #1 2016-08-25 05:40 Dear Sir or Madam, In the past we used the default Options in the JDO 1.0. See below for reference: ...

 
page

What is new in ObjectDB 2.0?

... of persistent classes that are not enhanced. Improved optimistic locking support. Performance improvement in writing and reading ...

 
api-jdo

begin()

Begin a transaction.(Method of javax.jdo.Transaction)

 
api-jdo

flush()

Flushes all dirty, new, and deleted instances to the data store.(Method of javax.jdo.PersistenceManager)

 
issue

Remove an entity which attributes were changed

We use an OSGi environment and we have three OSGi plugins.   In plugin A an entity is loaded and the entity is passed to plugin B. Plugin B changes an attribute on the entity. Plugin C removes the entity from the database. After commit the transaction an exception is caused with optimistic lock exception of the removed entity.   If this operations on the entity are executed in only one plugin, it works well.   ... After commit the transaction an exception is caused with optimistic lock exception of the removed entity.   If this ...

 
api-jdo

setIgnoreCache(ignoreCache)

Set the ignoreCache option.(Method of javax.jdo.Query)

 
api-jdo

checkConsistency()

Validates the PersistenceManager cache with the datastore.(Method of javax.jdo.PersistenceManager)

 
api-jdo

makeTransactional(pc)

Make an instance subject to transactional boundaries.(Method of javax.jdo.PersistenceManager)

 
api-jdo

getConnectionFactory2()

Get the second data store connection factory.(Method of javax.jdo.PersistenceManagerFactory)

 
api-jdo

setConnectionFactory2(connectionFactory)

Set the second data store connection factory.(Method of javax.jdo.PersistenceManagerFactory)