(Optional) The name of the map key column. The table in which it is found depends upon the context.
- If the map key is for an element collection, the map key column is in the collection table for the map value.
- If the map key is for a
ManyToManyentity relationship or for aOneToManyentity relationship using a join table, the map key column is in a join table. - If the map key is for a
OneToManyentity relationship using a foreign key mapping strategy, the map key column is in the table of the entity that is the value of the map.
Defaults to the concatenation of the following: the name of the referencing relationship field or property; "_"; "KEY".
- Default:
- ""
- Since:
- Jakarta Persistence (JPA) 1.0