两个不同实体中的相同@NamedQueries 会发出警告

Posted 2023-03-23

【中文标题】两个不同实体中的相同@NamedQueries 会发出警告

【英文标题】：Same @NamedQueries in two different entities gives warning

【发布时间】：2019-02-12 13:15:48

【问题描述】：

我在两个实体中有相同的@NamedQueries，如下所示：

@Table(name = "STUDENT_TABLE")
@NamedQueries( 
@NamedQuery(name = "getStudentById", query = "SELECT s FROM Student s where s.stdId=:stdId"),
@NamedQuery(name = "getStudentByName", query = "SELECT s FROM Student s where s.fName=:fName and s.lName =:lName")
)

@Table(name = "MARKS_TABLE")
@NamedQueries( 
@NamedQuery(name = "getStudentById", query = "SELECT s FROM Student s where s.stdId=:stdId"),
@NamedQuery(name = "getStudentByName", query = "SELECT s FROM Student s where s.fName=:fName and s.lName =:lName")
)

在处理上述问题时，我收到如下警告：

openjpa.MetaData: Warn: Ignoring duplicate query "getStudentById" in "class Student". A query with the same name been already declared in "class Marks".
openjpa.MetaData: Warn: Ignoring duplicate query "getStudentByName" in "class Student". A query with the same name been already declared in "class Marks".

这是什么原因，我们如何才能摆脱这个警告？

【参考方案1】：

@NamedQuery 的范围是整个持久性单元。 在不同实体上定义它们并不重要。

当您定义重复名称时，很可能在构建持久性单元期间其中一个名称将被覆盖。

好的做法是在命名查询前加上实体名称：

@NamedQuery(name = "Student.getStudentById"..
@NamedQuery(name = "Marks.getStudentById"...