Entity Framework: How To Properly Handle Exceptions That Occur Due To Sql Constraints

I use Entity Framework to access my SQL data. I have some constraints in the database schema and I wonder how to handle exceptions that are caused by these constraints. As example,

Solution 1:

You should be able to trap the SQL error number (which is SqlException.Number)

In this case it's 2627 which has been the same forever for SQL Server.

If you want abstraction, then you'll always have some dependency on the database engine because each one will throw different exception numbers and messages.

Solution 2:

One way is to inspect the Errors property of the inner SqlException. The SqlError class has a Number property that identifies the exact error. See the master.dbo.sysmessages table for a list of all error codes.

Of course this still ties you to Sql Server. I'm not aware of a way to abstract this away other than roll your own 'EF exception analyzer'.

Solution 3:

This scenario should not happen as the key should never be assign explicitly when using EF; rather allowing the context to assign an appropriate one. If its a concurrency issue then you should do the update in a transaction scope.

Then if you have an UpdateException you could retry the update again. You can safely do that in a transaction scope and only complete the scope when the update goes thorough. In this scenario the chances of the update going through the next time is greater than the first one.