blocks|key|931102|text|我自己也遇到了这个问题&当我用Googled搜索它的时候(我回答了你的问题)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|931103|我可以在设计器中双击这条线(关联线)。填写那里的属性，我就让它正常工作了。|931104|我还不得不关闭VS并重新打开它，以获得一些报告的错误。|931105|不能说这是正确的答案--只是笨手笨脚地摸索，似乎得到了结果。|931106|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|L|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|M|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

I just ran into this myself &amp; when I Googled it (I hit your question).

I was able to double click on the line (association line) in the designer. Fill in the properties there and I got it working.

I also had to close VS and re-open it to get some of the errors reported to go away...

Can't say this is the correct answer - just fumbling around and seeming to get results.

blocks|key|1145664|text|我也犯了同样的错误，“添加关联”对话框没有帮助我设置的一个配置是“引用约束”属性。一旦我进行了配置，我重新构建了解决方案，一切都很酷。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1145665|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I had the same error, and one bit of configuration that the "Add Association" dialog didn't help me set was the "Referential Constraint" property. Once I configured that I rebuilt the solution and everything was cool.

blocks|key|1145715|text|当我在安装了EF4.1的VS2010+SP1下使用ADO.Net+DBContext生成器从数据库生成模型时，我得到了这个错误。我使用的数据库在主键和外键字段之间没有任何引用完整性。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1145716|解决方案是双击关联线，这将打开Referential+Contstrainst对话框。然后，我将Principal字段设置为具有主键的表，将Dependent字段设置为具有外键的表，在下拉列表中设置要匹配的外键名称，然后单击OK。|1145717|然后编译代码，我可以使用var+foreign+=DBContext.Primary.First()、.Foreign等跨实体工作|1145718|史蒂夫|1145719|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|L|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|M|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

I got this error when I generated the model from the database using the ADO.Net DBContext Generator under VS2010 SP1 with EF4.1 installed. The database I was using did NOT have any referential integrity between the primary and foreign key fields.

The solution was to double click the association line which brings up the Referential Contstrainst dialog box. I then set the Principal field to be the table with the primary key, the Dependent as the table with the foreign key, set the foreign key names to match in the drop down and clicked OK.

The code then compiled and I was able to work across the entities using
var foreign = DBContext.Primary.First().Foreign etc

Steve

blocks|key|1145761|text|当我从模型图中删除了一个关联，但该关联仍然保留在.edmx的底层XML中时，我就遇到过这个错误。我找到的唯一修复方法是手动编辑edmx以删除对有问题的关联的引用。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1145762|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I've had this error when I've deleted an association from the model diagram but the association remains in the underlying XML in the .edmx. They only way I've found to fix that is to hand-edit the edmx to remove references to the offending association.

blocks|key|931303|text|您所要做的就是从edmx文件中删除所有的表。现在右击edmx文件并选择更新表单数据库选项。更新Ef，问题将得到解决。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|931304|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

All you just have to do is delete all your tables from edmx file. Now right click in edmx file and choose update form database option. Update Ef, issue will be resolved.

blocks|key|931338|text|我还发现，在更改实体框架上下文和模型后重新生成项目有时可以解决这些错误，特别是当实体框架上下文位于不同的项目中时。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|931339|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I have also found that rebuilding your project after changes to your Entity Framework context and models can sometimes resolve these errors, especially if the Entity Framework contexts are in a different project.

For a new project I'm trying to create my business classes first and create the real database tables later. Therefore I'm using the Entity Framework 4 Designer. A created a new "ADO.Net Entity Data model" file, with the extension .edmx.

I created two Entities: 
<img src="https://i.stack.imgur.com/w65e1.png" alt="alt text">

I want to add a 1 to nc relation between Product -> Group. If I'd created the MSSQL database first, I would have added a column IDGroup to the Table Product and referenced Product.IDGroup to Group.IDGroup. As far as I can see, I can't add such association in the designer if I add a new Property called IDGroup to the Product Entity

This is how I add the mapping:
<img src="https://i.stack.imgur.com/dcPvl.png" alt="alt text">

Which results in: 
<img src="https://i.stack.imgur.com/JQ8WB.png" alt="alt text">

Now the part what this question is about: If I add two tables from an existing MSSQL database to the edmx file, I'll get the compile error:

<pre><code>Error 3027: No mapping specified for the following EntitySet/AssociationSet - GroupSet, ProductSet
</code></pre>

What does that error mean and what must I do to fix this?
If I delete those two tables, I'll receive a warning instead:

<pre><code>Error 2062: No mapping specified for instances of the EntitySet and AssociationSet in the EntityContainer myContainer.
</code></pre>

Something tells me, I'm doing this all wrong and this is just basic stuff. How can I do it right?

How do I correctly set an association between two objects in the Entity Framework 4 Entitydesigner?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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对于一个新项目，我正在尝试先创建我的业务类，然后再创建真正的数据库表。因此，我使用Entity Framework4设计器。创建了一个扩展名为.edmx的新"ADO.Net实体数据模型“文件。我创建了两个实体：​我想在产品->组之间添加一个1到nc的关系。如果我首先创建了MSSQL数据库，我会在表Product中添加一...

问如何在Entity Framework4EntityDesigner中正确设置两个对象之间的关联？
EN

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问如何在Entity Framework4EntityDesigner中正确设置两个对象之间的关联？EN