实体框架DBFirst将表转换为关联，如何获取表访问权限？

Question

I have a DBFirst EntityFramework 6.1 solution that i'm trying to generate off of. When i add a table that only contains two foreign keys the table is turned into two associations and I can not directly access the table anymore. This is neat for navigation in the code but makes it a pain in the ass to delete records from the table.

Is there a way to prevent this behavior and gain direct access to the table as an entity?

For example i am unable to remove an entry in the association because i get this error

The operation failed: The relationship could not be changed because one or more of the foreign-key properties is non-nullable. When a change is made to a relationship, the related foreign-key property is set to a null value. If the foreign-key does not support null values, a new relationship must be defined, the foreign-key property must be assigned another non-null value, or the unrelated object must be deleted.

For example here is how my database sees the structure.

Here is how it appears in entity framework. Notice that the CorporateDataShareVisible table is missing and instead two new associations are created.

The CorporateDataShareVisible table should be able to be deleted and added to at will but any changes i make seem to stop it from working.

Answer 1

Add a primary key to your table that has only foreign keys. EF uses the primary key to keep track internally of the element. Without a primary key it doesnt know which element was modified and how to send that back to your RDBMS.

I prefer surrogate keys ie auto incrementing integers. You can also add the primary key by making it a composite key of both the foreign keys