虽然我也担心Java会取代自由形式的SQL查询，但我确实认为人们批评ORM是因为它的应用程序设计总体上很糟糕。

True OOD is driven by classes and relationships, and ORM gives you consistent mapping of different relationship types and objects. If you use an ORM tool and end up coding query expressions in whatever query language the ORM framework supports (including, but not limited to Java expression trees, query methods, OQL etc.), you are definitely doing something wrong, i.e. your class model most likely doesn't support your requirements in the way it should. A clean application design doesn't really need queries on the application level. I've been refactoring many projects people started out using an ORM framework in the same way as they were used to embed SQL string constants in their code, and in the end everyone was suprised about how simple and maintainable the whole application gets once you match up your class model with the usage model. Granted, for things like search functionality etc. you need a query language, but even then queries are so much constrained that creating an even complex VIEW and mapping that to a read-only persistent class is much nicer to maintain and look at than building expressions in some query language in the code of your application. The VIEW approach also leverages database capabilities and, via materialization, can be much better performance-wise than any hand-written SQL in your Java source. So, I don't see any reason for a non-trivial application NOT to use ORM.

当我在编写一个中等大小的JavaSE应用程序时，我对Avaje Ebean有过很好的体验。

它使用标准JPA注释来定义实体，但公开了一个更简单的API(没有EntityManager或任何附加/分离实体之类的废话)。它还允许您在必要时轻松使用SQL查询或事件纯JDBC调用。

它还为查询提供了一个非常好的流动和类型安全的API。你可以这样写:

List<Person> boys = Ebean.find(Person.class)
                                  .where()
                                       .eq("gender", "M")
                                       .le("age", 18)
                                  .orderBy("firstName")
                                  .findList();

我已经停止使用orm了。

原因并不是这个概念有什么大缺陷。Hibernate工作得很好。相反，我发现查询的开销很低，我可以将大量复杂的逻辑放入大型SQL查询中，并将大量处理转移到数据库中。

因此，请考虑只使用JDBC包。

虽然我也担心Java会取代自由形式的SQL查询，但我确实认为人们批评ORM是因为它的应用程序设计总体上很糟糕。

True OOD is driven by classes and relationships, and ORM gives you consistent mapping of different relationship types and objects. If you use an ORM tool and end up coding query expressions in whatever query language the ORM framework supports (including, but not limited to Java expression trees, query methods, OQL etc.), you are definitely doing something wrong, i.e. your class model most likely doesn't support your requirements in the way it should. A clean application design doesn't really need queries on the application level. I've been refactoring many projects people started out using an ORM framework in the same way as they were used to embed SQL string constants in their code, and in the end everyone was suprised about how simple and maintainable the whole application gets once you match up your class model with the usage model. Granted, for things like search functionality etc. you need a query language, but even then queries are so much constrained that creating an even complex VIEW and mapping that to a read-only persistent class is much nicer to maintain and look at than building expressions in some query language in the code of your application. The VIEW approach also leverages database capabilities and, via materialization, can be much better performance-wise than any hand-written SQL in your Java source. So, I don't see any reason for a non-trivial application NOT to use ORM.

我建议使用MyBatis。它是JDBC之上的一个薄层，它很容易将对象映射到表，并且仍然使用纯SQL，一切都在您的控制之下。

没有，因为ORM占用了太多的控制权，而且好处很小。当您必须调试使用ORM导致的异常时，所节省的时间很容易被浪费掉。此外，orm不鼓励开发人员学习SQL和关系数据库的工作方式，并将其用于自己的利益。