CODEWITHSUNDEEP
c#asp.netentity-frameworkasp.net-mvc-3
anthonypliu
anthonypliu

Reputation: 12437

How to update my entity framework

I have been updating my Entity Framework by simply right clicking and clicking on "update model from database". I usually go under the "Add" tab and then click the tables and click finish. I also use "refresh" sometimes as well. What are the differences between these? and also when I do refresh or add sometimes the entity comes out wrong or keeps some of the old information in cache, how can I just get the entity to match my database and clean out any of the old cached things.

Upvotes: 3

Views: 1691

Answers (3)

Ladislav Mrnka
Ladislav Mrnka

Reputation: 364249

Designer is not buggy and the reason why it doesn't handle some changes is because CSDL and some MSL modifications made by user are not overwritten. CSDL is the diagram you see in designer and MSL is the mapping of your entities and associations.

Believe me this is a big step forward comparing to Linq-to-sql where no update existed and you always had to delete everything including your changes when you wanted to refresh your model. If you made a lot of changes you can always delete your entity in EF designer as well. EF designer offers a choice to update or recreate (by deleting the old one).

Upvotes: 1

Yakimych
Yakimych

Reputation: 17752

Yes, you are right. The designer is a bit buggy and doesn't handle certain schema changes particularly well. As a rule, when I add a table to the database, I run Update model from database and select the table in the Add tab. Works fine. If I add a field to an existing table, I do Update model and Refresh. Works well too.

But if I add one field and remove another, or rename an existing field (as far as I remember), EF does not handle this correctly (added a new field but failed to remove the old one, and since the old one remained unmapped, the model validation failed). So in those more complex cases I usually delete the entity and then do Update model from database and Add it again.

The downside is that if you did make some changes (e.g. renamed some fields or navigational properties of the entity), you'll have to do those changes again.

Upvotes: 5

user220583
user220583

Reputation:

It doesn't clean out old items. You have to delete those yourself. On the positive side, Visual studio will give you an error when you compile, stating that a coloumn or two isn't mapped. The entity framework tool is more of a code generator. It generates classes based on the structure of your database, as opposed to being tied to the database for is't structure information.

Upvotes: 3

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