auto creation of sequence using hibernate tool

Question

I wanted to to generate sequence using hibernate tool ( pojo to sql). And definitely it works fine.

@GeneratedValue(strategy = GenerationType.SEQUENCE, generato         


        

Answer 1

I looked it up in the Hibernate sources (4.2.7). It is not possible to specify this with an annotation (neither JPA nor Hibernate).

However you can provide your own Dialect to achieve this.

public class MyOwnOracleDialect extends Oracle10gDialect {

    @Override
    protected String getCreateSequenceString(final String sequenceName, final int initialValue, final int incrementSize)
        throws MappingException {
        String createSequenceString = super.getCreateSequenceString(sequenceName, initialValue, incrementSize);
        return createSequenceString + " NOCACHE ORDER CYCLE"; // modify this string as you like
    }
}

Have an entity like this

@Entity
public class MyEntity {

    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "seqid-gen")
    @SequenceGenerator(name = "seqid-gen", sequenceName = "RTDS_ADSINPUT_SEQ", allocationSize = 1, initialValue = 0)
    @Column(name="id")
    private Long id;

    // ...

}

You can set your new Dialect as described in the Hibernate doc (http://docs.jboss.org/hibernate/orm/4.2/manual/en-US/html/ch03.html#configuration-optional-dialects)

Answer 2

I think you are looking for something like this

    <id name="pk_field" column="column_name">
        <generator class="sequence">
            <param name="sequence">sequence_name</param>
            <param name="parameters">START WITH 5 INCREMENT BY 10</param>
        </generator>
    </id>