EclipseLink/UserGuide/JPA/Basic JPA Development/Entities/Table

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Key API

• @Table

@Table

You can use the @Table annotation or <table> XML element to configure the table for an entity to do the following:

• define the name of the entity's table
• define the schema or catalog if your table is defined in a different schema than your connection and requires to be prefixed
• define unique constraints for DDL generation

@Table Attributes

Attribute	Description	Default	Required?
name	The name of the table	entity name (as uppercase)	No
catalog	A String catalog name.	Default catalog for database	No
schema	The String name of the schema.	Default schema of the database	No
uniqueConstraints	This is used only by DDL generation. By default only a primary key and foreign key constraints are defined, if desired set the value of this attribute to an array of one or more UniqueConstraint instances. For more information, see Section 11.1.49 "UniqueConstraint Annotation" in the JPA Specification.	No additional constraints	No

For more information, see Section 11.1.45 "Table Annotation" in the JPA Specification.

The following example shows how to use this annotation to specify the table for Employee.

Example: Using @Table

@Entity
@Table(name="EMP", uniqueConstraints = {@UniqueConstraint(columnNames={"SSN"})})
public class Employee implements Serializable {
    ...
    @Id
    public Long getId() {
        return id;
    }
    ...
}

Example: Using <table-generator>

<entity class="Employee">
    <table name="EMP">
        <unique-constraint>
            <column-name>SSN</column-name>
        </unique-constraint>
    </table>
    <attributes>
        <id name="id"/>
        ...
    </attributes>
</entity>

Views

It is possible to map an entity to a database view. To do this simply give the view name for the name in the @Table annotation.

Case Sensitively, Reserved Words and Special Characters

Some databases are case sensitive, but most are not. In general it is best to uppercase all table/column names to be portable. Most databases allow mixed cased names if you put the name in quotes. To do this use the " character when defining the table's name. Quotes also allow the usage of spaces, reserved words, and some special characters on most databases.

Example: Using quoted @Table

@Entity
@Table(name="\"Employee Data\"")
public class Employee implements Serializable {
    ...
    @Id
    public Long getId() {
        return id;
    }
    ...
}

Version: 2.2.0 DRAFT
Other versions...

@SequenceGenerator	Configuring Entities	@SecondaryTable
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