System data updateexception an error occurred while updating the entries

12-May-2016 03:08

This has the greatest amount of yak shaving because I would have to spin up mapping from the domain and to the domain. The nice thing is that with that kind of detail, naming mismatches can be handled and the nested hierarchy and choice types are accounted for. Sql Exception: The INSERT statement conflicted with the FOREIGN KEY constraint "fk_Pet_Child". To understand why this is problem then I need to describe how EF knows about the database schema.EF holds a view of what it thinks the database schema is in what it calls the ‘database model’.Another problem with using reflection is that the field names in the database need to match the domain naming exactly. Finally, like automapper, there is not out of the box way to map choice types Hand Roll On my last stop of the entity framework code-last hit parade, I looked at what it would take to roll my own mappings.

( I'm working on that and hope to get news about it soon.) So, for while, you have to create the database manually.

Feeling confident, I went ahead and created maps to all of the domain types and pulled down a complex type from the database Sure enough, reflection does what it is supposed to do: The problem quickly becomes that by using reflection, I have to hand roll all of the relations.

I might as well use Automapper (though apparently reflection is much faster than Automapper, even on a per-call basis).

The State is null because it is defined as “State Code” on the server and “State” in the domain.

Autopmapper is customizable to allow field name differences so that was a small issue.

One of the main useful things EF does is make a relational database look like a set of linked classes.