Creating Unique Keys in Entity Framework Code First
Entity Framework Code First allows you to manage database schemas by creating models and specifying relationships between them. However, by default, it does not provide a way to define unique constraints on fields.
Understanding Unique Keys in EF Code First
In EF Code First, a unique key ensures that a specific field or combination of fields must have unique values for each row in the database table. This helps prevent duplicate data and ensures data integrity.
Creating a Unique Key Using Custom Database Initialization
Prior to EF 6.1, creating a unique key required using a custom database initializer. Here's how you can implement it:
- Create a custom database initializer that inherits from CreateDatabaseIfNotExists
:
public class MyInitializer : CreateDatabaseIfNotExists<MyContext> { protected override void Seed(MyContext context) {
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