Discover Entity Framework Core for efficient data access. Gain insights into workflows, model configuration, querying, logging, and testing to boost productivity and code maintainability.

Using Entity Framework Core for Data Access & Relational Mapping.png

ScaffoldDB.tar.gz

EFCore

EFCorePreCreateTablesInOutputDir

EFCorePreCreateTablesAndViewInOutputDir

EFCoreWithProxies

EFCoreWithXunit

CreateSchoolTablesInOutputDir

This course introduces Entity Framework Core for data access and object-relational mapping. Entity Framework Core provides benefits such as the ability to work with databases using .NET objects without the concern for underlying database tables. This leads to less code for data access and improved performance. 

You’ll begin with the workflows of Entity Framework Core—reverse engineering and migrations. Next, you’ll learn model configuration and relationships. Then, you’ll cover various methods for querying and saving data. You’ll also learn about change tracking and its relationship with queries. Finally, you’ll learn about logging and testing.

Entity Framework Core simplifies app development. By the end of this course, you’ll be able to improve code maintainability and concentrate on business logic by generating SQL, materializing results, and performing other tasks. You’ll have a good understanding of Entity Framework Core, which will improve your productivity and efficiency on your development journey.

Using Entity Framework Core for Data Access & Relational Mapping

# Overview
The default conventions handle the most common configurations in the EF Core model, such as:

* Determining the table name of an entity.
* Determining the column name of an entity.
* Determining which property becomes the primary key of an entity.
* Determining which property becomes the foreign key in a relationship.
* Determining which entities make up a relationship.


Sometimes, the default conventions do not capture our model adequately, and we may need to configure the entities to meet our objectives. We can supplement or override the default conventions through two methods.

## Data annotations
**Data annotations** are simple attribute-based configuration methods where different .NET attributes are applied to domain classes and properties to configure the model.  The attributes are included in the `System.ComponentModel.DataAnnotations` and `System.ComponentModel.DataAnnotations.Schema` namespaces.

## Fluent API
We can override the `OnModelCreating` method in the derived context and use the `ModelBuilder API` to configure a model. The API uses method chaining based on the fluent API design pattern. The fluent API is a powerful approach, providing more functionality than data annotations. Unlike data annotations, the fluent API configures the model without modifying the domain classes.

> **Note:** The commands in this lesson generate code and files. Through the terminal, we can navigate to these files by using relevant Linux commands such as `ls` to view a list of files and directories, `cd` to change directories, and `cat` to view file contents. A SPA widget showing the updated project with the generated files is also available. Also, note that EF Core uses a timestamp within the generated file names. We represent these names with `xxx`.

# Default conventions
By convention, properties whose .NET types can be `null` are configured as optional, while properties whose .NET types cannot be `null` are configured as required. We demonstrate these conventions through the properties of the `Person` entity in the project below:


Learn about supplementing or overriding the default conventions in EF Core.

Getting Started

Reverse Engineering

Migrations

Configuring a Model

Query Data

Save Data

Logging and Testing

Build a REST API Using ASP.NET Core 6

Conclusion

Appendix

Supplementing Conventions in Entity Framework Core

Overview

Data annotations

Fluent API