Code First Data migration

Once the project is online, you need to make changes to the database and no longer use dropcreatedatabaseifmodelchanges

If you manually modify the DbContext or entity class, an error occurs:

Models that support the "entities" context have changed since the database was created. Consider migrating the update database using Code first.

Enter Enable-migrations in the package Manage console to enable the migration feature.

• add-migration would scaffold the next migration based on changes and made to your model since the last Migrat Ion was created

• Update-database 'll apply any pending migrations to the Database

Do not enable the migration feature, manually conform to the entity class changes to the database, delete the automatically generated table _mirgration in the database, the error will not be reported. Manually modifying the database is consistent with the changes to the entity class.

Code First Data migration