SecondaryTable (Java EE 5 SDK)

javax.persistence Annotation Type SecondaryTable

@Target(value=TYPE)
@Retention(value=RUNTIME)
public @interface SecondaryTable

This annotation is used to specify a secondary table for the annotated entity class. Specifying one or more secondary tables indicates that the data for the entity class is stored across multiple tables.

If no SecondaryTable annotation is specified, it is assumed that all persistent fields or properties of the entity are mapped to the primary table. If no primary key join columns are specified, the join columns are assumed to reference the primary key columns of the primary table, and have the same names and types as the referenced primary key columns of the primary table.

 Example 1: Single secondary table with a single primary key column.

    @Entity
    @Table(name="CUSTOMER")
    @SecondaryTable(name="CUST_DETAIL", 
        pkJoinColumns=@PrimaryKeyJoinColumn(name="CUST_ID"))
    public class Customer { ... } 

    Example 2: Single secondary table with multiple primary key columns.

    @Entity
    @Table(name="CUSTOMER")
    @SecondaryTable(name="CUST_DETAIL",
        pkJoinColumns={
            @PrimaryKeyJoinColumn(name="CUST_ID"),
            @PrimaryKeyJoinColumn(name="CUST_TYPE")})
    public class Customer { ... }
 

从以下版本开始:

Java Persistence 1.0

name

public abstract String name

(Required) The name of the table.

catalog

public abstract String catalog

(Optional) The catalog of the table.

Defaults to the default catalog.

默认值:

""

schema

public abstract String schema

(Optional) The schema of the table.

Defaults to the default schema for user.

默认值:

""

pkJoinColumns

public abstract PrimaryKeyJoinColumn[] pkJoinColumns

(Optional) The columns that are used to join with the primary table.

Defaults to the column(s) of the same name(s) as the primary key column(s) in the primary table

默认值:

{}

uniqueConstraints

public abstract UniqueConstraint[] uniqueConstraints

(Optional) Unique constraints that are to be placed on the table. These are typically only used if table generation is in effect. These constraints apply in addition to any constraints specified by the Column and JoinColumn annotations and constraints entailed by primary key mappings.

Defaults to no additional constraints.

默认值:

{}

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