JPA Eclipselink getting wrong sequence number

问题

I'm using some Entities mapped to Oracle DB-Tables. For ID-Generation I'm using a sequence generator annotated as following:

@Id
@SequenceGenerator(name = "SEQ_RULES", sequenceName = "SEQUENZ_RULES")
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SEQ_RULES")
@Column(name = "SERIALNO")
protected Long serialno;

During programm execution I make a new Instance from my Entity and want to persist this generated one. After restart of the database I'm getting wrong sequence numbers through JPA-EclipseLink, but not through the Console directly on the database.

I turned on following properties in the persistence.xml toget also the binding parameters used in the generated statements.

<properties>
  <property name="eclipselink.logging.level" value="FINE"/>
  <property name="eclipselink.logging.parameters" value="true"/>
</properties>

For example: If I generate a new instance of my entity and want to persist this one I get 2717 for serialNo and if I execute

SELECT SEQUENZ_RULES.NEXTVAL FROM DUAL

I get 2767 as nextval. The problem is that the JPA-generated serialNo must be unique, and now I stil have some datasets with this serialNo. Im getting an exception:

java.sql.SQLIntegrityConstraintViolationException: ORA-00001: unique constraint (JASON.SYS_C0084866) violated

Non Is there any caching through eclipse which is affecting the Sequence Generation or what could be the error for this?

Used Components:
GlassFish 3.1.1
EclipseLink 2.3.0.v20110604-r9504
Database: Oracle Version: Oracle Database 11g Release 11.1.0.7.0 - 64bit
Driver: Oracle JDBC driver Version: 11.2.0.1.0

Thanks in advance

Adem

回答1:

When you created the sequence you specified a size to increment by. For example this sequence increments by 1.

CREATE SEQUENCE supplier_seq
  MINVALUE 1
  MAXVALUE 999999999999999999999999999
  START WITH 1
  INCREMENT BY 1
  CACHE 20;

When using the SequenceGenerator annotation in JPA you can specify an allocation size.

@Id
@SequenceGenerator(name = "SEQ_RULES", sequenceName = "SEQUENZ_RULES",
    allocationSize=1)
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SEQ_RULES")
@Column(name = "SERIALNO")
protected Long serialno;

Make sure the allocation size and the increment match between JPA and the Sequence DDL.

回答2:

Change allocationSize=1 by allocationSize=2, it is a Eclipselink bug.

来源：https://stackoverflow.com/questions/15404636/jpa-eclipselink-getting-wrong-sequence-number

标签

java

jpa

eclipselink

Sequence