How do I change databases in Entity Framework?

How do I change databases in Entity Framework?

Change Entity framework database schema at runtime In most applications you can change the database store by modifing the connectionstring at runtime. i.e I can change from using a test database to a production database by simply changing the value of the “database” field in the connectionstring…

How do I change the state of entity using DB context?

This can be achieved in several ways: setting the EntityState for the entity explicitly; using the DbContext. Update method (which is new in EF Core); using the DbContext. Attach method and then “walking the object graph” to set the state of individual properties within the graph explicitly.

How do I update Entity Framework model from database first?

Update Model From Database To update model from the database, right-click the . edmx file and select Update Model from Database. Expand the Tables, Views, and Stored Procedures nodes, and check the objects you want to add to the . edmx file.

How do I update Entity Framework model after database change code first?

4 Answers

  1. Create a new Entity Data Model, call it StoreDBContextTemp or whatever.
  2. Choose the code first from database wizard option.
  3. Select customer as an object to add (just customer) & complete the wizard.

How do you modify EDMX if changes are made in the Database?

Delete existing model and then update: Delete key to delete all models in the designer. IMPORTANT: Do not save the EDMX at this point if you are using TFS for source control!* Now right-click and select “Update Model from Database” to recreate the entire model again. Rebuild project to propagate changes.

How do I add a column to an existing table in Entity Framework?

First attempt:

  1. Opened the Model in Visual Studio.
  2. Right Clicked on the Background.
  3. Clicked on “Update Model From Database…”
  4. Clicked on the Refresh Tab.
  5. Selected Tables.
  6. Highlighted the specific table.
  7. Clicked Finish.

How do I update my entity?

The steps to update an existing entity are quite simple. First retrieve an instance of the entity from the EntitySet (in our case ObjectSet), then edit the properties of the Entity and finally call SaveChanges() on the context.

How do I change state entity?

Changing the state of a tracked entity Note that calling Add or Attach for an entity that is already tracked can also be used to change the entity state. For example, calling Attach for an entity that is currently in the Added state will change its state to Unchanged.

How do you modify EDMX if changes are made in the database?

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

This could be done only when no Table depends on the table which you want to update.

  1. Delete the table which needs to be updated.
  2. 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.

How do you update-database code first?

Update an Existing Database using Code First Migrations with ASP.NET and Entity Framework

  1. Enable-Migrations -ContextTypeName CodeFirstExistingDB.StoreContext.
  2. Add-Migration InitialCreate -IgnoreChanges.
  3. namespace CodeFirstExistingDB.
  4. Add-Migration add_product_description.
  5. namespace CodeFirstExistingDB.Migrations.

How do I update existing migration?

If you want to apply a change from Migration2 onwards…

  1. Roll back to Migration1: Update-Database -TargetMigration Migration1 -Force (NB – This may cause data loss, so work on a development copy of your database)
  2. Make your model code match what you wanted for Migration 2, and update the code for Migration 2 by hand.