LinqToSQL - 映射出的DataContext有很多表？ [英] LinqToSQL - mapping out the DataContext with lots of tables?

问题描述

我一直对一个项目，我一直在使用 LinqToSQL ，涉及很多表。所有这些其中有一个的.dbml 文件映射（即只有一个的DataContext ）。我这样做的借口是（目前）你不能跨多个数据上下文加盟。例如...

I've been working on a project where I have been using LinqToSQL that involved a lot of tables. All of these where mapped in one .dbml file (i.e. only one DataContext). I did this on the pretense that (currently) you cant join across multiple data contexts. For example...

DB1DataContext db1 = new DB1DataContext();
DB2DataContext db2 = new DB2DataContext();

var query =
    from x in db1.SomeTable
    join y in db2.AnotherTable on x.Id equals y.Id
    select new
    {
        x.Column,
        y.Column
    };

有人认为，这是不是这样的，我应该打破。 DBML 文件分解成更小的独立（即更多的可管理）的数据上下文。我现在已经刚刚成立了一个例子，运行一个类似的查询上面的一个，得到了以下错误...

Someone argued that this isn't so, and I should break the .dbml file down into seperate smaller (i.e more managable) data contexts. I've now just set up an example, run a similar query to the one above and got the following error...

{基地System.SystemException} = {的
查询包含对不同数据上下文定义的项目
的引用。}

base {System.SystemException} = {"The query contains references to items defined on a different data context."}

我很好奇，我失去的东西吗？什么是那里有很多需要映射表的常见做法？你怎么能打破一个.dbml文件？

I am curious, am I missing something? What are the common practices where there are a lot of tables that require mapping? How can you break down a .dbml file?

推荐答案

这在这里问了几次，也没有明确的答案。选中此问题：

This was asked several times here and there is no definite answer. Check this questions:

• 的 LINQ to SQL的：每个项目多/单的.dbml


• 的是多方面的DataContext类有史以来适当


• 的 LINQ to SQL和大型数据库模型


• 的Managing LINQ到SQL的.dbml模型的复杂性


• 最佳实践管理LINQ to SQL的DBML文件？

• LINQ to SQL: Multiple / Single .dbml per project?
• Are Multiple DataContext classes ever appropriate?
• Linq to SQL and large DB model
• Managing LINQ to SQL .dbml model complexity
• Best Practices for Managing Linq to SQL Dbml Files?

一些答案​​请参阅此博客帖子：的一个LINQ的寿命到SQL的DataContext

Some answers refer to this blog post: Lifetime of a LINQ to SQL DataContext

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