A join table is typically used in the mapping of many-to-many and unidirectional one-to-many associations. It may also be used to map bidirectional many-to-one/one-to-many associations, unidirectional many-to-one relationships, and one-to-one associations (both bidirectional and unidirectional).
When a join table is used in mapping a relationship with an embeddable class on the owning side of the relationship, the containing entity rather than the embeddable class is considered the owner of the relationship.
If the JoinTable
annotation is missing, the default
values of the annotation elements apply. The name of the join
table is assumed to be the table names of the associated primary
tables concatenated together (owning side first) using an
underscore.
Example:
@JoinTable(
name = "CUST_PHONE",
joinColumns = @JoinColumn(name = "CUST_ID", referencedColumnName = "ID"),
inverseJoinColumns = @JoinColumn(name = "PHONE_ID", referencedColumnName = "ID"))
- Since:
- 1.0
- See Also:
-
Optional Element Summary
Modifier and TypeOptional ElementDescription(Optional) The catalog of the table.(Optional) Check constraints to be applied to the table.(Optional) A comment to be applied to the table.(Optional) Used to specify or control the generation of a foreign key constraint for the columns corresponding to thejoinColumns()
element when table generation is in effect.Index[]
(Optional) Indexes for the table.(Optional) Used to specify or control the generation of a foreign key constraint for the columns corresponding to theinverseJoinColumns()
element when table generation is in effect.(Optional) The foreign key columns of the join table which reference the primary table of the entity that does not own the association.(Optional) The foreign key columns of the join table which reference the primary table of the entity owning the association.(Optional) The name of the join table.(Optional) A SQL fragment appended to the generated DDL statement which creates this table.(Optional) The schema of the table.(Optional) Unique constraints to be placed on the table.
-
Element Details
-
name
String name(Optional) The name of the join table.Defaults to the concatenated names of the two associated primary entity tables, separated by an underscore.
- Default:
""
-
catalog
-
schema
String schema(Optional) The schema of the table.Defaults to the default schema for user.
- Default:
""
-
joinColumns
JoinColumn[] joinColumns(Optional) The foreign key columns of the join table which reference the primary table of the entity owning the association. (I.e. the owning side of the association).Uses the same defaults as for
JoinColumn
.- Default:
{}
-
inverseJoinColumns
JoinColumn[] inverseJoinColumns(Optional) The foreign key columns of the join table which reference the primary table of the entity that does not own the association. (I.e. the inverse side of the association).Uses the same defaults as for
JoinColumn
.- Default:
{}
-
foreignKey
ForeignKey foreignKey(Optional) Used to specify or control the generation of a foreign key constraint for the columns corresponding to thejoinColumns()
element when table generation is in effect. If both this element and theforeignKey
element of any of thejoinColumns()
elements are specified, the behavior is undefined. If no foreign key annotation element is specified in either location, a default foreign key strategy is selected by the persistence provider.- Since:
- 2.1
- Default:
@jakarta.persistence.ForeignKey(PROVIDER_DEFAULT)
-
inverseForeignKey
ForeignKey inverseForeignKey(Optional) Used to specify or control the generation of a foreign key constraint for the columns corresponding to theinverseJoinColumns()
element when table generation is in effect. If both this element and theforeignKey
element of any of theinverseJoinColumns()
elements are specified, the behavior is undefined. If no foreign key annotation element is specified in either location, a default foreign key strategy is selected by the persistence provider.- Since:
- 2.1
- Default:
@jakarta.persistence.ForeignKey(PROVIDER_DEFAULT)
-
uniqueConstraints
UniqueConstraint[] uniqueConstraints(Optional) Unique constraints to be placed on the table. These are only used if table generation is in effect.Defaults to no additional constraints.
- Default:
{}
-
indexes
Index[] indexes(Optional) Indexes for the table. These are only used if table generation is in effect.- Since:
- 2.1
- Default:
{}
-
check
CheckConstraint[] check(Optional) Check constraints to be applied to the table. These are only used if table generation is in effect.- Since:
- 3.2
- Default:
{}
-
comment
String comment(Optional) A comment to be applied to the table. This is only used if table generation is in effect.- Since:
- 3.2
- Default:
""
-
options
String options(Optional) A SQL fragment appended to the generated DDL statement which creates this table. This is only used if table generation is in effect.- Since:
- 3.2
- Default:
""
-