使用基类中定义的属性过滤条件 [英] Filter condition using attributes defined in base class

问题描述

我有3类 Base ， Child 和 Other 定义如下:

I have 3 classes Base, Child and Other defined as follows:

@Entity
@Filter(name = "myFilter", condition = "propBase = 'special'")
@Inheritance(strategy = InheritanceType.JOINED)
public abstract class Base {
   private String propBase;

   //Getters, Setters
}

@Entity
public class Child extends Base {
   private String propChild;

   //Getters, Setters
}

@Entity
public class Other {
   @Filter(name = "myFilter", condition = "propBase = 'special'")
   private Set<Child> myList;

   //Getters, Setters
}

假定过滤器是在包级别定义的，因此使用它的所有类都可以看到它.

Assume the filter is defined at the package level so it is visible by all the classes that use it.

使用启用了 myFilter 的会话，我从数据库中检索了 Other 的某些实例.然后，当我尝试访问 myList 集合时，由于该集合被声明为惰性的，因此Hibernate尝试从数据库中获取该集合.但是，在生成的SQL查询中我没有想到的事情:表 Child 的别名用​​于为 propBase 列添加前缀，并且由于该列不是定义在表 Child (在 Base 中定义)中，出现以下错误:

Using a session with myFilter enabled, I retrieve some instance of Other from my database. Then, when I try to access the myList collection, since the collection is declared as lazy, Hibernate tries to fetch the collection from the database. But, there is something that I didn't expect in the generated SQL query: the alias of table Child is used to prefix the propBase column, and since this column is not defined in the table Child (it is defined in Base), I get the following error:

错误JDBCExceptionReporter-中的未知列'childAlias.propBase'"where子句"

ERROR JDBCExceptionReporter - Unknown column 'childAlias.propBase' in 'where clause'

根据此线程，它似乎是预期的行为，但我不知道该怎么做.另外，假设这是预期的行为，当条件使用基类中定义的属性时如何使用过滤?

According to this thread, it seems to be the expected behavior but I don't understand how it can be. Also, assuming this is the expected behavior, how to use filtering when the condition uses properties defined in base class?

谢谢

推荐答案

您需要使用sql片段别名- https://docs.jboss.org/hibernate/orm/5.4/userguide/html_single/Hibernate_User_Guide.html#pc-filter-sql-fragment-alias

You need to use sql fragment alias - https://docs.jboss.org/hibernate/orm/5.4/userguide/html_single/Hibernate_User_Guide.html#pc-filter-sql-fragment-alias

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