问题描述
我使用的是使用Visual Studio 2012 Express的Entity Framework 5.0第一种方法。我有一个方案来生成一个可空的外键。例如，有两个实体 - 组织和用户。并非所有用户都属于组织。但是，一些用户将属于一个组织。尽管改变了多重性，但是 User.Organization_ID 列总是 not null 请帮我解决这个问题。欣赏它。
I'm using Entity Framework 5.0 model-first approach using Visual Studio 2012 Express. I have a scenario to generate a nullable foreign key. For example, there are two entities – Organization and User. Not all users will belong to an organization. However, some users would belong to an organization. The User.Organization_ID column is always not null in spite of changing the multiplicity. Please help me to resolve this issue. Appreciate it.
推荐答案
更改多重性0..1 - > *（很多）修复了此问题。即0或1个组织可以具有0个或更多个用户。这样，用户表中的organizatio_id就被生成为可空的列！感谢大家帮忙！
Changing the multiplicity 0..1 --> * (many) fixed this issue. i.e. 0 or 1 organization can have 0 or more users. This way, the organizatio_id in the user table is generated as nullable column! Thanks everyone for helping!
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