根据我的理解，适配器模式基本上是在另一个类上创建一个包装器，以便现有代码可以使用您正在包装的类。外观用于更改整个子系统（因此，如果您正在处理需要 5 个步骤的复杂绘图 api，您可以将它们合并为仅 1 个方法，例如）。那么我的问题是 ORM 使用哪种模式，还是两者都使用？
它们为许多不同的子系统提供了一个接口，但我仍然不确定，尽管我倾向于外观模式。
From my understanding the Adapter pattern is basically creating a wrapper on another class so that the class you are wrapping can be used by existing code. A facade is for changing an entire subsystem (so if you are dealing with a complicated drawing api that requires 5 steps you might consolidate them into just 1 method, as an example). My question then is which pattern do ORM's use, or is it both?
They provide a single interface into many different subsystems but I'm still not sure, though I'm leaning towards the facade pattern.
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对于我所了解的ORM框架来说，Adapter似乎并不是一个至关重要的模式。可以使用外观，例如在 Hibernate/JPA 中，其中有一个 Session/EntityManager 接口负责几乎所有事情，可能在幕后调用许多不同的子系统接口。
然而，还有很多其他模式在发挥作用。 工厂 模式经常使用，几乎不用说:-)另一个突出的模式（至少在 Hibernate 中）是 代理，这是延迟获取的基础。此外：对象池（用于数据库连接）、解释器（用于查询）...该列表可以继续。
For the ORM frameworks I know, Adapter does not seem to be a crucial pattern. Facade may be used, e.g. in Hibernate/JPA where there is a single Session/EntityManager interface responsible for almost everything, probably calling a lot of distinct subsystem interfaces behind the curtain.
However, there is a lot of other patterns in play. That the Factory patterns are used often is almost needless to say :-) Another prominent one (in Hibernate at least) is Proxy, which is fundamental in lazy fetching. Furthermore: Object Pool (for the DB connections), Interpreter (for queries)... the list could be continued.