Hello,

I have a hibernate setup with 50+ objects. For some tables I have multiple objects in the same table, hence I use a 'discriminator' to distinguish the objects.

Now, how can I go about adding an index to the discriminator column?

I am using MySQL 5 with InnoDB tables.

I have tried...

@Entity
@Table(name="PersistObject",uniqueConstraints = @UniqueConstraint(columnNames = {"manufacturer", "partNumber"}))
@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(
name="type",
discriminatorType=DiscriminatorType.CHAR,
columnDefinition="CHAR(1) CHARACTER SET utf8 COLLATE utf8_bin"
)
@DiscriminatorValue("4")
@org.hibernate.annotations.Table(appliesTo = "PersistObject", indexes = @org.hibernate.annotations.Index(name = "type_index", columnNames = "type"))

to no avail. I have also tried editing the xml config but with no results.

Your input would be greatly appreciated.

Thanks,
Omid S

Are you using Hibernate to create your schema SQL or are you connecting to an existing database. In the second case simply use the MySQL tools to create the index. Hibernate only need to know about the index if you want Hibernate to generate the schema SQL for you.