ObjectDB Database Search

Pessimistic lock

WORM (Write once read many) support

Internal ObjectDB error by read the primary key

Failed to read the value of field using reflection (error 363)

Have read read the documentation on optimistic locks, still not sure how to deal ... . But you can disable optimistic locking in the server configuration .   support Support read the documentation ... - since someone can change the object just after the refresh . In that case - use pessimistic locks. support

The best source for learning ObjectDB is the ObjectDB Manual , which contains all the necessary information for using ObjectDB. The only required background is a good understanding of the Java language. Reading the manual and getting started with ObjectDB could be easier for developers with prior

Please read the ObjectDB licence page.

: access - permission to open a database for read . modify - permission to modify the content

This chapter demonstrates basic ObjectDB and JPA concepts by introducing a simple example program. After reading this chapter you should be able to write basic programs that create, open and close ObjectDB databases and perform basic CRUD operations (Create/Store, Retrieve, Update and Delete

create the readings in one call and I try to read them in another call. I checked the database and all the entities are created (document and readings ) but when I try to get the collection of readings null is returned. I have tried to clear the entity manager in the second call to make sure the reading

to the transaction PessimisticLockException - if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking fails and only the statement is rolled ... has not been joined to the transaction PessimisticLockException - if pessimistic locking fails

PessimisticLockException - if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking fails and only the statement is rolled back PersistenceException - if the query ... to the transaction PessimisticLockException - if pessimistic locking fails and the transaction is rolled

and with specified properties. If a pessimistic lock mode type is specified and the entity contains a version ... is pessimistic and the entity instance is found but cannot be locked: the PessimisticLockException ... transaction EntityNotFoundException - if the entity does not exist in the database when pessimistic

the persistence context with the specified lock mode type. If a pessimistic lock mode type is specified ... will be thrown. If the lock mode type is pessimistic and the entity instance is found but cannot be locked ... transaction EntityNotFoundException - if the entity does not exist in the database when pessimistic

is pessimistic and the entity has a version attribute, the persistence provider must perform optimistic ... will be thrown. If the lock mode type is pessimistic and the entity instance is found but cannot be locked ... OptimisticLockException - if the optimistic version check fails PessimisticLockException - if pessimistic locking

there. If the entity is found within the persistence context and the lock mode type is pessimistic and the entity ... mode type is pessimistic and the entity instance is found but cannot be locked ... OptimisticLockException - if the optimistic version check fails PessimisticLockException - if pessimistic

is pessimistic and the entity instance is found but cannot be locked: the PessimisticLockException will be thrown ... EntityNotFoundException - if the entity no longer exists in the database PessimisticLockException - if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking fails

. If the lock mode type is pessimistic and the entity instance is found but cannot be locked ... EntityNotFoundException - if the entity no longer exists in the database PessimisticLockException - if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking fails

JPA Enum PessimisticLockScope java.lang.Object ∟  java.lang.Enum ∟  javax.persistence.PessimisticLockScope Defines the values of the javax.persistence.lock.scope property for pessimistic ... for pessimistic locking. The persistence provider must lock the database row(s) that correspond

the persistence context has not been joined to the transaction PessimisticLockException - if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking fails

has not been joined to the transaction PessimisticLockException - if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking fails

- if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking

been joined to the transaction PessimisticLockException - if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking fails and only the statement

- if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking

the persistence context has not been joined to the transaction PessimisticLockException - if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking fails

has not been joined to the transaction PessimisticLockException - if pessimistic locking fails and the transaction is rolled back LockTimeoutException - if pessimistic locking fails and only the statement

JPA Enum Constant in javax.persistence.PessimisticLockScope NORMAL This value defines the default behavior for pessimistic locking. The persistence provider must lock the database row(s) that correspond to the non-collection-valued persistent state of that instance. If a joined inheritance

when EntityManager.lock is used with pessimistic locking is used and the entity no longer exists in the database

JPA Exception LockTimeoutException java.lang.Object ∟  java.lang.Throwable ∟  java.lang.Exception ∟  java.lang.RuntimeException ∟  javax.persistence.PersistenceException ∟  javax.persistence.LockTimeoutException Thrown by the persistence provider when an pessimistic

when an pessimistic locking conflict occurs. This exception may be thrown as part of an API call, a flush or at commit

when data is read from the database and when data is committed into the database. Since: JPA 2.0 ... insert into cache. Since: JPA 2.0 REFRESH Insert/update entity data into cache when read from database and when committed into database. Forces refresh of cache for items read from database. Since: JPA

server and open the database file in ObjectDB Explorer : This is the end of the tutorial. Learn more about ObjectDB and JPA by reading the Manual .

of the tutorial. Learn more about ObjectDB and JPA by reading the Manual .

enabled without specifying a Java agent. This is the end of the tutorial. Learn more about ObjectDB and JPA by reading the Manual .

getReadOnly () Gets the value for read -only for this PMF. Indicates whether the datastore is read -only or ... (boolean flag) Sets the value for whether the datastore is to be considered read -only. ReadOnly ... are: read -uncommitted read -committed repeatable- read snapshot serializable Parameters: level

() If true , allows persistent instances to be read without a transaction active. Return: the value ... an implementation but are not standard. Standard values in order of low to high are: read -uncommitted read -committed repeatable- read snapshot serializable Parameters: level - the transaction isolation level

JDO Interface Constants Constant values used in JDO. Since: JDO 2.1 Public Static Fields TX_ READ _COMMITTED Transaction isolation level representing the requirement to read committed data ... () Since: JDO 2.2 TX_ READ _UNCOMMITTED Transaction isolation level representing the ability to read

from low to high are: read -uncommitted read -committed repeatable- read snapshot serializable ... _ READ _UNCOMMITTED Constants.TX_ READ _COMMITTED Constants.TX_REPEATABLE_ READ Constants.TX_SNAPSHOT Constants.TX_SERIALIZABLE Since: JDO 2.2

values in order of low to high are: read -uncommitted read -committed repeatable- read snapshot ... _ READ _UNCOMMITTED Constants.TX_ READ _COMMITTED Constants.TX_REPEATABLE_ READ Constants.TX_SNAPSHOT Constants.TX_SERIALIZABLE Since: JDO 2.2

.GetDataStoreConnection javax.jdo.option.UnconstrainedQueryVariables javax.jdo.option.TransactionIsolationLevel. read -uncommitted javax.jdo.option.TransactionIsolationLevel. read -committed javax.jdo.option.TransactionIsolationLevel.repeatable- read javax.jdo.option.TransactionIsolationLevel.snapshot javax.jdo.option

JDO Method in javax.jdo.PersistenceManagerFactory boolean getReadOnly () Gets the value for read -only for this PMF. Indicates whether the datastore is read -only or writable. Return: the readOnly setting. See Also: setReadOnly Since: JDO 2.2

readExternal (ObjectInput in) Read this object. Read the superclass first. Parameters: in - the input

JDO Method in javax.jdo.identity.IntIdentity void readExternal (   ObjectInput in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

(ObjectInput in) Read this object. Read the superclass first. Parameters: in - the input

JDO Method in javax.jdo.identity.CharIdentity void readExternal (   ObjectInput in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

JDO Method in javax.jdo.identity.ObjectIdentity void readExternal (   ObjectInput in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

Since: JDO 1.0 void readExternal (ObjectInput in) Read this object. Read the superclass first

JDO Method in javax.jdo.identity.LongIdentity void readExternal (   ObjectInput in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0

Since: JDO 1.0 void readExternal (ObjectInput in) Read this object. Read the superclass first

JDO Method in javax.jdo.identity.ByteIdentity void readExternal (   ObjectInput in ) Read this object. Read the superclass first. Parameters: in - the input Since: JDO 1.0