The typical method is to look up the entity by its primary key, because that will guarantee a unique result.
典型的方法是根据实体的主关键字进行查询，因为这可以保证产生一个独一无二的结果。
An entity's primary key is the attribute or set of attributes that distinguish one instance of the entity from another.
实体的主键是使该实体的一个实例区别于其他实例的一个或一组属性。
Multiple attributes in the entity may be combined to form a composite primary key.
实体中的多个属性可以组合成一个复合的主键。
On the primary key Tasks page, select deptno as the primary key for the Department entity.
在主要关键字Tasks页面中，选择deptno以作为Department实体的主要关键字。
The relationship is represented by a new CMP entity bean called Attendee, having two fields (three if we count the primary key field).
用名为attendee的新CMP实体bean表示关系，该bean有两个字段(如果加上主键字段则有三个)。
Each record saved in the datastore, also called an entity, requires a primary key.
保存在数据存储中的每一条记录，即实体，都需要有一个主键。
We also use a primary key class, constructed from the values comprising the EJB primary key, to make it easy to specify the primary key as a single entity.
我们还使用由组成ejb主键的值构建的主键类使得把主键指定为一个单独的实体很容易。
In this test, we created a single entity named OgisCustomer, which has four member attributes including the primary key (SRCSEQ).
在该测试中，我们创建了一个名为ogiscustomer的实体，它有包括主键(SRCSEQ)在内的4个成员属性。
That is, if concurrent transactions update an entity bean with same primary key, updates could get lost.
如果并发事务用同样的主键更新实体bean 时，更新资料将会丢失。
For example, if account Numbers are assigned across all types of accounts, account type may need to be used along with account Number to form the primary key of the accounts entity.
例如，如果所有类型的账户都被指定一个AccountNumber，那么可能需要使用AccountType和AccountNumber一起作为Accounts实体的主键。
The simplest way to access persistent data is by using the find method. Here is an example of an application using the entity manager to find an object by its primary key.
最简单的访问持久性数据的方法是使用find方法。
If the database has a table without a primary key, the entity data Model tools try to infer a key for the corresponding entity.
如果数据库中有一个未设置主键的表，那么实体数据模型工具会尝试为相应的实体推断一个键。
For an entity class, at least one member must have this attribute and should be mapped to the primary key or a unique key in the corresponding table or view.
对于实体类，必须至少有一个成员具有此特性，并应映射到相应表或视图中的主键或唯一键。
For an entity class, at least one member must have this attribute and should be mapped to the primary key or a unique key in the corresponding table or view.
对于实体类，必须至少有一个成员具有此特性，并应映射到相应表或视图中的主键或唯一键。
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