ASP.NET Core Model-View-Controller (MVC) provides several approaches for building web applications. Here are some of the main approaches:

Database First approach

The Database-First approach in ASP.NET Core MVC involves designing the database schema first, and then using code-generation tools to generate the code for the application based on the database schema.

This approach is well suited for applications that need to work with existing databases, and it provides a more structured and defined approach to database development.

How to use Database-First approach

• Design the database schema:This involves defining the tables, columns, relationships, and constraints in the database. You can use tools such as SQL Server Management Studio (SSMS) to design the schema.
• Create the database: Once the schema has been designed, you can create the database by executing the SQL scripts that define the schema.

• Generate the Entity Framework Core (EF Core) model: You can use the EF Core reverse engineering tool to generate an EF Core model from the database schema. This model represents the database in your application code and provides a convenient way to interact with the database.

• Generate the MVC controllers and views: You can use scaffolding to generate the MVC controllers and views that provide the user interface for the application. Scaffolding generates the basic CRUD (Create, Read, Update, Delete) operations for the application based on the EF Core model.

• Customize the generated code: Once the scaffolded code has been generated, you can customize it to add additional functionality and behavior to the application.

• Test and deploy the application: Once the code has been generated and customized, you can test the application and then deploy it to a production environment.

How to generate database using database first approach ?

Step:1 Create the database

This involves creating the database schema and the necessary tables and relationships. You can use a database management tool such as SQL Server Management Studio (SSMS) to create the database.

Step:2 Install the EF NuGet package

You need to install the EF NuGet package in your ASP.NET MVC project.

You can do this by running the following command in the Package Manager Console:

PM>Install-Package EntityFramework

Step:3 Create the EF data model

Now, create the EF data model based on the database schema.

Running the following command in the Package Manager Console:

PM>Scaffold-DbContext "Server=(localdb)\mssqllocaldb;Database=MyDatabase;Trusted_Connection=True;"

PM>Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models

Above command generates the EF data model, including the classes and properties that represent the tables and columns in the database, as well as the DbContext class that represents the database.

Step: 4 Generate the MVC controllers and views

You can use scaffolding to generate the MVC controllers and views that provide the user interface for the application.

Scaffolding generates the basic CRUD (Create, Read, Update, Delete) operations for the application based on the EF data model.

You can do this by running the following command in the Package Manager Console:

PM>Scaffold-Controller -DbContext MyDbContext -ControllerName CustomersController -ControllerDir Controllers

Code-First approach in ASP.NET Core MVC

code-generation tools to generate the database schema based on the code.

• Define the entities and their relationships: This involves defining the classes that represent the entities in your application, and the relationships between these entities.

• Configure the Entity Framework Core (EF Core) model: You can use EF Core attributes and fluent API to configure the EF Core model and define the database schema. This includes defining the tables, columns, relationships, and constraints in the database.

• Generate the database: Once the EF Core model has been defined, you can use EF Core migrations to generate the database schema and create the database.

• Generate the MVC controllers and views: You can use scaffolding to generate the MVC controllers and views that provide the user interface for the application. Scaffolding generates the basic CRUD (Create, Read, Update, Delete) operations for the application based on the EF Core model.

• Customize the generated code: Once the scaffolded code has been generated, you can customize it to add additional functionality and behavior to the application.

• Test and deploy the application: Once the code has been generated and customized, you can test the application and then deploy it to a production environment.

creating the code for the application first, and then using Entity Framework Core (EF Core) to generate the database based on the code.

Execute the following Command In Package Manager Console in Visual Studio:

Step:1 Install the EF Core NuGet package

install the EF Core NuGet package in your ASP.NET Core MVC project.

You can do this by running the following command in the Package Manager Console:

PM>Install-Package Microsoft.EntityFrameworkCore

Step:2 Create the EF Core data model

You need to create the EF Core data model by defining the classes and properties that represent the tables and columns in the database.

Step:3 Create the DbContext class

You need to create the DbContext class that represents the database.

The DbContext class is the primary class for interacting with the database and contains information about the database connection and the data model classes.

Step:4 Enable EF Core migrations

You need to enable EF Core migrations in your ASP.NET Core MVC project.

You can do this by running the following command in the Package Manager Console:

PM>Add-Migration InitialCreate

Above command generates a code-based migration that creates the initial database schema based on the EF Core data model.

Step: 5 Update the database

You can use the following command in the Package Manager Console to update the database with the latest schema changes:

PM>Update-Database

Model-First approach in ASP.NET MVC

The Model-First approach in ASP.NET MVC involves designing the database schema and the EF Core model in parallel, and then using code-generation tools to generate the code for the application based on the model. This approach provides a good balance between control over the database schema and structure, and flexibility in the application code.

steps involved in using the Model-First approach in ASP.NET MVC:

• Design the EF Core model: This involves defining the classes that represent the entities in your application, and the relationships between these entities. You can use the Entity Framework Designer (EF Designer) in Visual Studio to design the EF Core model.

• Generate the database schema: Once the EF Core model has been designed, you can use EF Core migrations to generate the database schema and create the database.

• Generate the MVC controllers and views: You can use scaffolding to generate the MVC controllers and views that provide the user interface for the application. Scaffolding generates the basic CRUD (Create, Read, Update, Delete) operations for the application based on the EF Core model.

• Customize the generated code: Once the scaffolded code has been generated, you can customize it to add additional functionality and behavior to the application.

• Test and deploy the application: Once the code has been generated and customized, you can test the application and then deploy it to a production environment.