Aug 08, 2017 This time no sequence is generated, instead an additional table named 'HIBERNATESEQUENCES' is created to maintain primary key sequence. GenerationType.IDENTITY This GenerationType indicates that the persistence provider must assign primary keys for the entity using a database identity column. Learn about Identity, Sequence, and Table in Hibernate. In my previous post I talked about different database identifier strategies. This post will compare the most common surrogate. May 17, 2013 GenerationType.SEQUENCE in hibernate generates the sequence for the primary column of the table. We need to create a sequence generator in database and refer that name in the code. The syntax of GenerationType. SEQUENCE is given below. Since Oracle doesn’t have auto-increment feature for primary key, you must use sequence instead. Use the following annotation for mapping the primary key field in a model class: @GeneratedValue(strategy = GenerationType.SEQUENCE). You can use SQLPlus or SQL Developer tool to create the sequence. Hibernate Example Program For your.
Hibernate JPA Sequence(non-Id) (9)
'I don't want to use a trigger or any other thing other than Hibernate itself to generate the value for my property'
In that case, how about creating an implementation of UserType which generates the required value, and configuring the metadata to use that UserType for persistence of the mySequenceVal property?
Unique Key
Is it possible to use a DB sequence for some column that is not the identifier/is not part of a composite identifier?
I'm using hibernate as jpa provider, and I have a table that has some columns that are generated values (using a sequence), although they are not part of the identifier.
What I want is to use a sequence to create a new value for an entity, where the column for the sequence is NOT (part of) the primary key:
Then when I do this:
the id will be generated, but the
mySequenceVal property will be also generated by my JPA provider.
Just to make things clear: I want Hibernate to generate the value for the
mySequencedValue property. I know Hibernate can handle database-generated values, but I don't want to use a trigger or any other thing other than Hibernate itself to generate the value for my property. If Hibernate can generate values for primary keys, why can't it generate for a simple property?
After spending hours, this neatly helped me to solve my problem:
For Oracle 12c:
Sequence Generated Primary Key In Hibernate Example For Kids
For H2:
Start Hibernate Sequence
Also make:
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