Hibernate generates negative id values when using a sequence
Solution 1
I just ran into this issue when migrating from JBoss 6.1 to JBoss 7.1.
According to the JBoss AS 7.1 JPA documentation ( https://docs.jboss.org/author/display/AS71/JPA+Reference+Guide#JPAReferenceGuide-Persistenceunitproperties),
JBoss 7.1 automatically sets several hibernate properties. One of the properties being set is hibernate.id.new_generator_mappings
which activates new ID generators that use different algorithms and are not backwards compatible. Setting this property to false in your persistence.xml file will restore the old ID generator behavior.
The hibernate 4 documentation also has information regarding the new ID generators: http://docs.jboss.org/hibernate/core/4.0/manual/en-US/html_single/#mapping-declaration-id-generator.
The hibernate documentation clearly states that the new ID generators are not enabled by default, but, as noted above, JBoss 7.1 is automatically enabling them.
Solution 2
The new behaviour is the followings:
AllocationSize is a range of primary key values reserved for Hibernate.
And the select seq.nextval
from dual will be done only after hibernate consumed this range of primary keys.
So you must declare the same value on both allocationSize
(Hibernate) and sequence increment by
(DB)
When explicitly set allocationSize=500
, e.g. on Oracle
create sequence SEQ_ACE_WORKERS_QUEUE_STATS_ID
MINVALUE 1
MAXVALUE 999999999999999999999999999
START WITH 1
INCREMENT BY 500
NOCACHE
NOCYCLE;
Otherwise, you'll notice negative values or constraint errors raised from your DB because of primary key collisions.
When the app server is restarted, you'll notice the 'jump' between the latest primary key allocated, and the 'newly' sequence number selected at restart.
Final comment: default value is 50. So if you don't specify allocationSize
on the Hibernate side, you must declare increment by
50 on the DB side.
Solution 3
Setting hibernate.id.new_generator_mappings
to false
in my persistence.xml
was just the first part of the solution to my problem:
To completely solve the problem I added the allocationSize
to 1
in the @SequenceGenerator
(which I was omitting).
Related videos on Youtube
Tomer
Updated on July 09, 2022Comments
-
Tomer almost 2 years
I have a class with the following definition:
@Id @SequenceGenerator(name = "SEQ_ACE_WORKERS_QUEUE_STATS_ID", sequenceName = "SEQ_ACE_WORKERS_QUEUE_STATS_ID", allocationSize = 500) @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SEQ_ACE_WORKERS_QUEUE_STATS_ID") @Column(name = "ID") private long Id;
When we ran it on Jboss 4.2.3 it worked fine and generated the proper ID's (starting from 1000+)
Now we moved to jboss 7.1.1 and it generates negative ID's! (starting from -498 and going up)
Any idea why this might happen?
-
HRgiger about 12 yearsdid you check what is current sequence in Oracle and trace hibernate output, if you see proper select next sequence query and if you copy paste into sqlplus you get the correct/same/expected result?
-
-
Tomer almost 12 yearsThanks for the answer, I already managed to find it, forgot to update it here :(
-
Markus Pscheidt over 6 yearsStarting with Hibernate version 5.0, the
hibernate.id.new_generator_mappings
property defaults totrue
. See docs.jboss.org/hibernate/orm/5.2/userguide/html_single/… -
Markus Pscheidt over 6 yearsVery useful answer, as this information apparently isn't in the Hibernate docs.
-
Spork over 5 yearsbut why did you have to add both? What part of the new_generator_mappings besides the allocationSize change gave an issue that was solved by setting it to false?
-
falsarella over 5 yearsSetting to false just worked after setting allocationSize
-
MrtN almost 4 yearsThis helped me a lot. I couldn't get the @SequenceGenerator to work, because I kept getting negative values and constraint errors. Just adding allocationSize = 1 solved it. I am using PostgreSQL.