UniqueConstraint (Java EE 5 SDK)

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Java EE 5 SDK

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摘要: REQUIRED | OPTIONAL

详细信息: ELEMENT

javax.persistence Annotation Type UniqueConstraint

@Target(value={}) @Retention(value=RUNTIME) public @interface UniqueConstraint

This annotation is used to specify that a unique constraint is to be included in the generated DDL for a primary or secondary table.

    Example:
    @Entity
    @Table(
        name="EMPLOYEE", 
        uniqueConstraints=
            @UniqueConstraint(columnNames={"EMP_ID", "EMP_NAME"})
    )
    public class Employee { ... }

从以下版本开始:: Java Persistence 1.0

Required Element Summary
`String[]`	`columnNames` (Required) An array of the column names that make up the constraint.

元素详细信息

columnNames

public abstract String[] columnNames

(Required) An array of the column names that make up the constraint.

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