EF automatically updates the database by modifying the model and efmodel automatically updates the database.

EF automatically updates the database by modifying the model and efmodel automatically updates the database.

Recently, when I used MVC + EF to learn how to modify the model and the database was not updated, I found an error on the Internet about automatic database update for data migration. After a long time, I finally got it.

Step 1: In the Package Manager Console: Enable-Migrations-ProjectName the name of the project where EF is located

Step 2: After running, the Migrations folder will be generated in the field. In the Migrations-> Configuration. cs class, set AutomaticMigrationsEnabled to true (that is, the database will be automatically updated when the model is changed)

If a field is deleted, add AutomaticMigrationDataLossAllowed = true (the value of data loss during Automatic migration is acceptable)

Step 3: In OwnDbContext

Public OwnDbContext (): base ("DefaultConnection") {Database. SetInitializer (new MigrateDatabaseToLatestVersion <OwnDbContext, Own. Model. Migrations. Configuration> ());}

PS: there are no third steps in some of the materials to be queried, but I still have to report an error or change it if I don't change it.