blocks|key|3253696|text|后来我发现，在我添加/更改/删除实体的属性之后，我必须在编译之前“从模型生成数据库”，否则我会得到3004个映射错误。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3253697|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|$]]

Have since discovered that after I add/change/delete properties on my entities I must "Generate Database from Model" before I compile otherwise I get 3004 mapping errors.

blocks|key|3039601|text|如果您所有的查询都是用存储过程编写的，而您只是试图填充模型，那么您可以切换到复杂类型，这对我很有效。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3039602|如何创建复杂类型：|3039603|3039604|手动将您遇到问题的实体生成的类的名称更改为edmx文件中尚未使用的名称。|ordered-list-item|3039605|选择模型浏览器窗口，然后右键单击/添加新的复杂type.|3039606|Copy/Paste将原始模型的属性映射到复杂类型。|3039607|将存储过程映射到复杂类型。|3039608|3039609|我希望这对某些人有帮助。|3039610|entityMap^0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|U|8|@]|9|@]|A|$]]|$1|E|3|F|5|G|7|V|8|@]|9|@]|A|$]]|$1|H|3|I|5|G|7|W|8|@]|9|@]|A|$]]|$1|J|3|K|5|G|7|X|8|@]|9|@]|A|$]]|$1|L|3|M|5|G|7|Y|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|10|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|R|$]]

If all your queries are written in stored procedures and you are just trying to fill the model then you could switch to a complex type which worked for me.

How to create a complex type:

<ol>
<li>Manually change the name of the
Entity Generated class you are
having issues with to a name not
already in use in your edmx file.</li>
<li>Select the Model Browser window and
right-click/add a new complex type.</li>
<li>Copy/Paste the properties of the
original model to the complex type.</li>
<li>Map your stored procedures to the
complex type.

I hope this helps someone.</li>
</ol>

blocks|key|305526|text|我只是从模型中删除了有问题的表，然后将它们添加回来，一切都很正常。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|305527|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 just removed the offending tables from the model and then added them back and all was well.

blocks|key|3039717|text|对于那些正在从数据库创建模型的人来说，我在对数据库进行更改后遇到了这个问题。当我出于这样或那样的原因在数据库中更改了字段名时，就会发生这种情况(我认为如果更改数据类型也会发生这种情况)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3039718|对我来说，解决方案是右键单击工作区，然后选择“从数据库更新模型”。这应该会将属性从DB添加到您的模型中，但是，它不会删除您的旧属性，这些属性会给出3004错误。|3039719|在工作区上单击鼠标右键，然后选择“验证”。这将为您提供一个错误列表，其中显示了有问题的属性。然后，您可以右键单击每个有问题的属性，并手动将其从模型中删除。|3039720|这为我解决了这个问题。希望这对其他人有帮助。|3039721|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|$]]

For those of you who are creating a model from a database, I had this issue after I made changes to my DB. It happened when I changed a field name in the DB for one reason or another (I think it also happens if you change a data type).

The solution, for me, was to right-click on the workspace and choose "Update Model from Database". This should add the properties from the DB to your model, however, it does NOT remove your old properties and those will give you the 3004 error.

Right-click on the workspace and choose "Validate". This should give you an error list showing the offending properties. You can then right-click each offending property and delete it manually from your model.

This fixed the issue for me. Hope it helps someone else.

blocks|key|305559|text|在重命名其中一个实体上的属性后，我收到了同样的问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|305560|我发现我的实体的属性和表中相应列之间的映射没有设置。|305561|您可以使用编辑器设置此设置，方法是右键单击模型中的实体并选择"Table+mapping“。确保属性映射到数据库中的列。|305562|编辑:我还需要重新运行我的tt文件来生成新的类。(可能是因为我在另一个项目中使用了它？)|305563|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 received the same problem after renaming a property on one of my entities.

I found out that the mapping between the property of my entity and the corresponding column in the table was not set.

You can set this using the editor by right clicking on the entity in the model and choosing "Table mapping". Make sure the properties are mapped to a column in the database.

Edit: I also needed to re-run my tt file to generate the new classes. (Might have been since I have it in another project?)

blocks|key|308512|text|在检查了xml文件(edmx)后，将模型移动到另一个项目，并意识到一切正常，我决定关闭并打开Visual+Studio，重新编译，然后错误消失。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|308513|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|$]]

After review the xml file (edmx), move the model to another project and realize that all is ok, I decided to close and open the Visual Studio and complile againt, then error disapears.

blocks|key|305582|text|如果您想在不重新生成整个模型或从模型中重新创建数据库的情况下修改数据库，我发现通过Visual+Studio修改EDMX图表中的属性，然后手动调整visual+studio不允许访问的映射是最简单、最安全的方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|305583|该错误将给出一个行号：|305584|映射从569行开始的片段时出现|offset|length|style|BOLD|305585|问题|blockquote|305586|305587|305588|只需在文本编辑器中打开edmx文件，转到该行，就会很明显地看到需要修复的内容。有一个部分将如下所示：|305589|<EntityTypeMapping+TypeName="YourModel.YourType">
++<MappingFragment+StoreEntitySet="YourType">
++++<ScalarProperty+Name="PropertyName1"+ColumnName="DatabaseColumn1"+/>
++++<ScalarProperty+Name="PropertyName2"+ColumnName="DatabaseColumn2"+/>
++++...
++</MappingFragment>
</EntityTypeMapping>|code-block|syntax|javascript|305590|只需确保所需的每个属性/列名都有一个节点，并且所有属性也列在edmx文档顶部的<EntityType+Name="YourTable">部分中|CODE|305591|entityMap^0|0|0|3|3|0|0|0|0|0|0|13|T|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|11|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|12|8|@$F|13|G|14|H|I]]|9|@]|A|$]]|$1|J|3|K|5|L|7|15|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|16|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|17|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|18|8|@]|9|@]|A|$]]|$1|Q|3|R|5|S|7|19|8|@]|9|@]|A|$T|U]]|$1|V|3|W|5|6|7|1A|8|@$F|1B|G|1C|H|X]]|9|@]|A|$]]|$1|Y|3|-4|5|6|7|1D|8|@]|9|@]|A|$]]]|Z|$]]

If you want to modify your database without regenerating the entire model or recreating your database from the model, I find it's easiest and safest to amend the properties in the EDMX diagram via Visual Studio and then manually adjust the mappings which visual studio doesn't give access to.

The error will give you a line number:

<blockquote>
 Problem in mapping fragments starting at line 569
</blockquote>

Just open the edmx file in a text editor, go to that line and it should be quite obvious what needs fixing. There's a section which will look like this:

<pre><code>&lt;EntityTypeMapping TypeName="YourModel.YourType"&gt;
 &lt;MappingFragment StoreEntitySet="YourType"&gt;
 &lt;ScalarProperty Name="PropertyName1" ColumnName="DatabaseColumn1" /&gt;
 &lt;ScalarProperty Name="PropertyName2" ColumnName="DatabaseColumn2" /&gt;
 ...
 &lt;/MappingFragment&gt;
&lt;/EntityTypeMapping&gt;
</code></pre>

Just make sure there's a node for each property/column name you need, and that all properties are also listed in the <code>&lt;EntityType Name="YourTable"&gt;</code> section at the top of the edmx document

blocks|key|306467|text|不从图表中删除表并重新添加的另一种方法是使用table+Mapping选项。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|306468|306469|转到模型浏览器|ordered-list-item|306470|右键单击表名称。|306471|Choose+tablle+mapping|306472|Visual+Studio将显示一个窗口，其中的EF属性匹配/缺少表columns.|306473|Select/match适当的列到缺少的属性|306474|306475|​|306476|📷|atomic|offset|length|306477|306478|entityMap|0|IMAGE|mutability|IMMUTABLE|imageUrl|https://ask.qcloudimg.com/http-save/yehe-900000/a0959d561d1cccde165e348ef326a5ab.png|imageAlt^0|0|0|0|0|0|0|0|0|0|0|1|0|0|0^^$0|@$1|2|3|4|5|6|7|15|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|16|8|@]|9|@]|A|$]]|$1|C|3|D|5|E|7|17|8|@]|9|@]|A|$]]|$1|F|3|G|5|E|7|18|8|@]|9|@]|A|$]]|$1|H|3|I|5|E|7|19|8|@]|9|@]|A|$]]|$1|J|3|K|5|E|7|1A|8|@]|9|@]|A|$]]|$1|L|3|M|5|E|7|1B|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|1C|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|1D|8|@]|9|@]|A|$]]|$1|Q|3|R|5|S|7|1E|8|@]|9|@$T|1F|U|1G|1|1H]]|A|$]]|$1|V|3|P|5|6|7|1I|8|@]|9|@]|A|$]]|$1|W|3|-4|5|6|7|1J|8|@]|9|@]|A|$]]]|X|$Y|$5|Z|10|11|A|$12|13|14|-4]]]]

Another alternative to do so without removing table from diagram and re-adding it, is by using Table Mapping option.
<ol>
<li>Goto to the model browser</li>
<li>Right click on table name.</li>
<li>Choose tablle mapping</li>
<li>Visual Studio will show a window with EF properties matching/missing table columns.</li>
<li>Select/match appropriate column to missing property</li>
</ol>
<a href="https://i.stack.imgur.com/uWhAY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/uWhAY.png" alt="enter image description here" /></a>

I have an Entity Framework 4 model-first design. I create a first draft of my model in the designer and all was well. I compiled, generated database, etc.

Later on I tried to add a string scalar (Nullable = true) to one of my existing entities and I keep getting this type of error when I compile:

<blockquote>
 Error 3004: Problem in mapping
 fragments starting at line 569: No
 mapping specified for properties
 MyEntity.MyValue in Set MyEntities. An
 Entity with Key (PK) will not
 round-trip when: Entity is type
 [MyEntities.MyEntity]
</blockquote>

I keep having to manually open the EDMX file and correct the XML whenever I add scalars.

Ideas on what's going on?

Entity Framework 4 mapping fragment error when adding new entity scalar

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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我有一个实体框架4模型优先的设计。我在设计器中创建了模型的第一个草稿，一切都很好。我编译，生成数据库，等等。后来，我尝试将字符串标量(Nullable = true)添加到现有实体之一，但在编译时不断收到这种类型的错误：错误3004:从第569行开始映射片段时出现问题:没有为Set MyEntities中的属性MyEn...

问添加新实体标量时Entity Framework 4映射片段错误
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