当未修改外键值时，UPDATE语句与FOREIGN KEY约束冲突

Question

I am using SQL through C# to make an update to a row in a table as shown below

context.AssessmentInvitation.Attach(assessmentInvitation);
context.Entry(assessmentInvitation).State = EntityState.Modified;
await context.SaveChangesAsync();

When this is executed in some cases, I get an exception on SaveChangesAsync due to a foreign key constraint. The foreign key constraint has to do with a CompanyId as part of the assessmentInvitation object being updated. This constraint is set to cascade on update, which seems to be the common solution to this issue. This did not resolve the issue for me.

The interesting thing is that the update causing this issue is not touching this foreign key at all. It is only updating a BIT to set it to true. No other values are being modified. The BIT is not related to any other table in any way, it is not part of any type of key.

Why would this foreign key constraint be relevant to the update at all if it is remaining the same? How can I fix this issue?

edit: The problem was much more simple than I thought. It was using a stored procedure that was not fetching the entire AssessmentInvitation object. Actually, it excluded the CompanyId completely. So when I tried to update without the existing CompanyId, obviously it failed. I thought I was going to learn something about Entity Framework, instead I realized I'm not very good at going through other people's code.

Answer 1

I can't add a comment so I'm posting an answer hope it helps you,

try to inspect the properties of assessmentInvitation to see if it holds a correct companyId value, if you are creating the object or created by the model binder in request it may has it's CompanyId set to null.