Note that this time, EF detects that the database already exists. You're now ready to add your first migration! Instruct EF Core to create a migration named InitialCreate: If you're more comfortable working inside Visual Studio or have experience with EF6 migrations, you can also use the Package Manager Console tools.NET Core CLI tools, which work on all platforms. Install the toolsįirst, you'll have to install the EF Core command-line tools: Let's assume you've just completed your first EF Core application, which contains the following simple model: public class Blogĭuring development, you may have used the Create and Drop APIs to iterate quickly, changing your model as needed but now that your application is going to production, you need a way to safely evolve the schema without dropping the entire database. Consult the other pages in this section for more in-depth information. The rest of this page is a step-by-step beginner's guide for using migrations. EF Core records all applied migrations in a special history table, allowing it to know which migrations have been applied and which haven't. Once a new migration has been generated, it can be applied to a database in various ways.EF Core compares the current model against a snapshot of the old model to determine the differences, and generates migration source files the files can be tracked in your project's source control like any other source file. When a data model change is introduced, the developer uses EF Core tools to add a corresponding migration describing the updates necessary to keep the database schema in sync.The migrations feature in EF Core provides a way to incrementally update the database schema to keep it in sync with the application's data model while preserving existing data in the database.Īt a high level, migrations function in the following way: In real world projects, data models change as features get implemented: new entities or properties are added and removed, and database schemas need to be changed accordingly to be kept in sync with the application.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |