实体框架4不遵守数字字段的数据库约束 [英] Entity Framework 4 not respecting database constraints for numeric fields

问题描述

说，我在DB中有一个表定义如下

表：Foo

PkId - int，primary，autoincrement

Bar - int，allow null = false，no default

现在，从数据库生成EF模型时，'Bar'字段被正确定义为Nullable =现在，当我执行以下操作时：

  var foo = new Foo（）; 
 context.AddToFoos（foo）; 
 context.SaveChanges（）; 
  

该行被插入到数据库中，Bar的值为0？我会期待一个例外，因为Bar尚未设置。我意识到0不是null，但也不是我设置的值。

这是设计还是我误解了某些东西？

解决方案

它不可空，因此是一个int。 int的默认值为0.所以DB很高兴，框架也很好。

Say, I have a table in the DB defined as follows

Table: Foo
PkId - int, primary, autoincrement
Bar - int, allow null=false, no default

Now when generating the EF model from the database the 'Bar' field is correctly defined as Nullable=false, Type=Int32.

Now when I do the following

var foo = new Foo();  
context.AddToFoos(foo);  
context.SaveChanges();

The row is inserted into the database and 'Bar' has a value of 0? I would have expected an exception because Bar hasn't been set. I realise that 0 isn't null but its also not a value that I've set.

Is this by design or have I misunderstood something?

解决方案

It's not nullable and thus an int. The default of int is 0. So the DB is happy and the framework is fine as well.

这篇关于实体框架4不遵守数字字段的数据库约束的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！