Entity framework 4 updating the model when a table changes - entity-framework

I am using Entity Framework 4.
I have my model file with my tables on it. If I go and add a new column to one of my tables (in SQL Server) how do I update the table in the model without having to go and delete and re-adding it to the model?
Thanks

There is an option when you right click anywhere in the model (*.edmx): Update Model From Database...
Then a wizard will look for any differences (Add / Refresh / Delete). So if you need to update a table, go to the Refresh tab and select your table.
Mind you, this is only possible in an Entity Framework model, not in a LinqToSql model.

Related

Can't select the database when updating EF model

I have an edmx model
I right click on it and select Update model from database
The wizard show up .It normally show me Choose Your Data Connexion, but not anymore. Now it show me directly Choose Your Database Objects
How can I select a different database ?
PS: When I create a second edmx in the same project and want to update it, the second one works like it should
After some trials, I found it.
You must delete the connection string in your config file (app.config in my case)

Cant add table to data model EF6

I have a data model and later I added 2 new tables. Both of these new tables have primary keys defined and the two tables also have relations. When I go to update the data model and add these two new tables, they are not listed. Im tempted to delete the model and recreate, but surely there is a better way. Im using VS 2012 (update 4) and EF6

Entity Framework - Entity not added to design surface

I attempted to update my edmx file by selecting a table. The tool spit out a info message that said the table did not have a primary key.
The entity did not get added to the design surface but it did get added to the .edmx file. In addition, using the model browser I see an Entities.Store and an Entities. My table got added to Entities.Store, but not to Entities.
I cannot access the table that was "added" in the code.
What do I do?
Steps to reproduce:
Create a SQL table with two columns that are both defined as foreign keys to other tables. Make sure the tables that the FKs point to already exist in the model on the design surface.
Right click and choose Update Model from Database...
Next. Under the Add tab, mark the new table under Tables
Click Finish.
An association will be created and it will be selected on the design surface, but it won't start with FK_, it will just be the name of your table. Go to the Model Browser and look under Entity Types. The table will not be there. Look under Associations and you will see your table name there as an association, but it will look out of place (because of the name).
Entity Framework was too smart for me. It created an association instead of an entity. Odd, but it works for how I need to use it.

How to update only one table for model from database with Entity Framework?

I have a model generated from db with Entity Framework. When I have any change in database, I update model from database to get the change in model. But this update is applied to all entities (tables) included in model.
Now I add a new column in a table Tab1. I don't want to update model from database as some other changes that I don't want to include in model. I can add the new property in model for entity Tab1 manually. then it caused mapping error.
So I need to update Model.Store for the table to include the new column. It means I want to update model only for Tab1.
How can I do this?
The EDMX file is an XML file that is a combination of 3 different parts that make up the whole thing. If you right-click on your EDMX file and choose "Open with... XML Editor" you'll see the 3 different sections:
<edmx:ConceptualModels>
<edmx:StorageModels>
<edmx:Mappings>
These sections can be edited manually, at your own risk! :-)
That way you can modify only what you need to.
Note that it's also possible to generate CSDL, SSDL & MSL files rather than having them embedded in the binary file, by changing the "Meta Artifact Processing" property of your model to "Copy to Output Directory".
If you don't want to do this manually, there's the Huagati DBML/EDMX tool, it is free and you can download it from huagati official site or from visual studio gallery, which is a Visual Studio plugin that allows you to select what changes need to be done.
I use following (Conditional) trick. This could be done only when no Table depends on the table which you want to update.
Delete the table which needs to be updated.
Right click on Model and select 'Update Model From Database'. The Table would be shown in the tab 'Add'. Select this table and Update the model.
Precaution : If other existing tables have changes in them, EF would update these changes as well.
There is way of doing it automatically.
right click edmx file > update model from data base > Refresh tab > Tables > select the table(you want to update) and press finish that's it.

MVC Entity Type Missing

I'm brand new to ASP.NET MVC (Literally just two days of learning on the fly). I'm trying to create a website using MVC, however, I've screwed something up in my solution.
I created this table that had foreign key constraints but I initially forgot to set up a primary key on the id field and forgot to set it identity specification to yes. So when I updated my DataModel and brought this table in, it showed every field as being the primary key and it showed the relationship to the other tables. So I went back to the database and changed the id field for the table to be the primary key and identity specification to yes.
I went back to the DataModel, tried to Update Model From Database, went to the refresh tab, expanded the tables, and selected the table I wanted to refresh, then click on "Finish".
The data model appeared to make the changes but it showed the relationships to the other tables twice.
So I thought I'd delete the table (entity) from the DataModel diagrahm and bring the table back in through Update Model From Database. But when I went back to the Update Model From Database...
Under the Add tab, the table isn't under the Tables
Under the Refresh tab, the table is listed, but when I select it and click on "Finish" the table doesn't reaapear in the diagrahm.
In the model browser...
Under Models
Entity Types, The entity isn't listed
Under Associations, The relationships no longer appear (obviously because the entity is gone).
Under Models.Store
Tables/Views, The table is listed.
Constraints, the relationships are shown.
I've tried dragging the table over to the diagrahm from the Model Browser, but that doesn't appear to work.
I've tried to right click in the diagrahm, add Entity but my table doesn't appear as a Base Type.
I've tried to google but I'm coming up with nothing. With this entity missing, I cannot even build my solution. Please help.
Try to delete the entity file and add it again. But you have to name it as previous entity and don't forget to delete the connectionString in web.config before add it.
If you don't know what I am saying just let me know.