具有多个后端和不同数据库设计的数据访问层(Data Access Layer with Multiple Backends and Different Database Designs)

 我正在开始一个项目，并且正在为我们的数据访问层而苦苦挣扎。 基本上它需要与不同数据库设计的多个后端接口。 
 
 我想要一个通用的DAL，然后在任何后端执行一个通用功能。 后端具有用于插入，更新等的唯一代码。因此，在1个后端中添加一个Employee将在另一个代码中具有不同的代码。 
 
 我尝试了Repository模式，但这并不适用于这种情况。 我已经结束了一个工厂模式的方法，但我最终会为每个对象创建一个工厂。 我可能只能创建1个工厂，但后端对象将具有数百个函数，如“SaveEmployee”，“SavePlan”等。 
 
 现在我有以下几点： 
 
DAL
    --> DAL.Backend1
        --> Employee.Save(employee)
        --> Plan.Save(plan)
    --> DAL.Backend2
        --> Employee.Save(employee)
        --> Plan.Save(plan)
 
 在DAL项目中，我为每个对象，员工，计划都有一个工厂模式，以决定返回并执行哪个DAL对象。 
 
 我很确定这不是最好的架构，所以我想知道是否有更好的模式来解决我的问题。 

I am starting a project and am struggling with the architecture for our data access layer. Basically it will need to interface with multiple backends with different database designs.
 
I would like a common DAL, which then executes a common function in any backend. The backends have unique code for inserting, updating, etc. So adding an Employee in 1 backend will have different code in another.
 
I tried the Repository pattern but that just doesn't apply to the situation. I've ended up with just a Factory pattern method, but I will end up creating a Factory for each object. I could maybe only create 1 factory but then the Backend object would have hundred of functions like "SaveEmployee", "SavePlan", etc.
 
Right now I have the following:
 
DAL
    --> DAL.Backend1
        --> Employee.Save(employee)
        --> Plan.Save(plan)
    --> DAL.Backend2
        --> Employee.Save(employee)
        --> Plan.Save(plan)
 
In the DAL project I have a Factory pattern for each Object, Employee, Plan, to decide which DAL's Object to return and execute against.
 
I am pretty sure this is not the best architecture for this, so I am wondering if there's a better pattern to use to solve my problem.

原文：https://stackoverflow.com/questions/14508077