Exam 70-487 topic 1 question 66 discussion

EAC, not D. We don't need to drop all our database to modify only altered tables.

I think A C E are correct answers.

I dont like the answear ECD ... I dont think you can choose C und D together. You have to pick one of them. You either: 1 - drop the database and create the new one or 2 - writing code in your migrations to perform a table rebuild.... so that you dont drop the database and create it again. I think the corect answear is: EDB

Lots of confusion here. My primary answer was BCE, but after consideration I think it should be BDE because of the limitations of SQL Lite: https://docs.microsoft.com/en-us/ef/core/providers/sqlite/limitations Since it is NOT specified what kind of changes are made to the model and one should RELIABLY handle the entity framework migration I think only way to do that is to drop and re-create the DB from scratch. So I think BDE is the correct answer. E,D,B, in that order.

CABE as says "u must apply the changes to the database." and command todo so is "Update-Database: Executes the last migration file created by the Add-Migration command and applies changes to the database schema." . Link https://www.entityframeworktutorial.net/code-first/code-based-migration-in-code-first.aspx

CED are correct. Explanation for D is here: https://docs.microsoft.com/en-us/ef/core/providers/sqlite/limitations "You can workaround some of these limitations by manually writing code in your migrations to perform a rebuild. Table rebuilds involve creating a new table, copying data to the new table, dropping the old table, renaming the new table. You will need to use the Sql(string) method to perform some of these steps."

E: Run dotnet ef migrations add InitialCreate to scaffold a migration and create the initial set of tables for the model. C: You can workaround some of the SQLite limitations by manually writing code in your migrations to perform a table rebuild. A table rebuild involves renaming the existing table, creating a new table, copying data to the new table, and dropping the old table. D: SQLite does not support all migrations (schema changes) due to limitations in SQLite. For new development, consider dropping the database and creating a new one rather than using migrations when your model changes.

What about an existing tables? C option is creating new tables and after update-database it will be conflict.

I think that CEB 1) modify script to migration to create new table 2) dotnet ef migrations add <script> 3) dotnet ef database update https://docs.microsoft.com/en-us/ef/core/providers/sqlite/limitations#migrations-limitations-workaround https://docs.microsoft.com/ru-ru/ef/core/managing-schemas/migrations/?tabs=dotnet-core-cli#customize-migration-code