Why I can't catch SqlException on SaveChanges() method of Entity Framework

Question

I put SaveChanges() method inside a try/catch block, but I couldn't catch SqlExeption.

try
 { 
     db.SaveChanges();
 }
 catch (Exception ex)
 {
 }

Answer 1

SqlException is System.Data.SqlClient.SqlException class so it's normal that you can't catch this exception The EntityFramework DbContext.SaveChanges Method() can throw the following exceptions only as by MSDN

DbUpdateException
DbUpdateConcurrencyException    

DbEntityValidationException 

NotSupportedException   

ObjectDisposedException 


InvalidOperationException    

So you can do something like this for example

try
 { 
     db.SaveChanges();
 }
 catch (DbUpdateException ex)
 {
 }
catch (DbUpdateConcurrencyException ex)
 {
 }

More
The exceptions mentioned above are entity Framework Customized exceptions that only EF is responsible on When and How to trigger Them take a look at Implementing custom exceptions

Answer 2

You cannot catch SqlException because it is not thrown directly, it is set as Inner Exception of the DbUpdateException.

Entity Framework is a abstraction to work with the databases, it does not depend on any Database technology directly.

Have a look at the Exceptions thrown by DbContext.SaveChanges()