The above command will revert the database based on a migration named MyFirstMigration and remove all the changes applied for the second migration named MySecondMigration.Migration is a way to keep the database schema in sync with the EF Core model by preserving data.
Enable Migrations Visual Studio Entity Update The DatabaseAs per the above figure, EF Core API builds the EF Core model from the domain (entity) classes and EF Core migrations will create or update the database schema based on the EF Core model.Whenever you change the domain classes, you need to run migration to keep the database schema up to date.
EF Core migrations are a set of commands which you can execute in NuGet Package Manager Console or in dotnet Command Line Interface (CLI). The following table lists important migration commands in EF Core. At the very first time, you defined the initial domain classes. At this point, there is no database for your application which can store the data from your domain classes. Open the Package Manager Console from the menu Tools - NuGet Package Manager - Package Manager Console in Visual Studio and execute the following command to add a migration. In the above commands, MyFirstMigration is the name of a migration. This will create three files in the Migrations folder of your project, as shown below. Enable Migrations Visual Studio Entity Code For CreatingThe Up() method includes the code for creating DB objects and Down() method includes code for removing DB objects. This is used to determine what changed when creating the next migration. Now, after creating a migration snapshot, its time to create the database. ![]() The Update command will create the database based on the context and domain classes and the migration snapshot, which is created using the add-migration or add command. If this is the first migration, then it will also create a table called EFMigrationsHistory, which will store the name of all migrations, as and when they will be applied to the database. You can remove the last migration if it is not applied to the database. Use the following remove commands to remove the last created migration files and revert the model snapshot. The above commands will remove the last migration and revert the model snapshot to the previous migration. Please note that if a migration is already applied to the database, then it will throw the following exception. If the migration has been applied to other databases, consider reverting its changes using a new migration. Suppose you changed your domain class and created the second migration named MySecondMigration using the add-migration command and applied this migration to the database using the Update command. But, for some reason, you want to revert the database to the previous state. In this case, use the update-database command to revert the database to the specified previous migration snapshot.
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