It is used to express the relationship between two tables. However, the fluent api is forcing me to create the virtual property in the ApplicationUser entity. ... EF Fluent API + two column composite uniqueness + autoincrement primary key. The ForeignKey attribute is used to specify which property is the foreign key in a relationship. EF Core 2.2 - Two foreign keys to same table. 925. Also, updated to EF 1.1.0-preview1. So for EF-core only option 3 is feasible. Entity Framework Code First - Defining Foreign Keys using Data Annotations and Fluent API When using Entity Framework Code First approach, there are actually three ways to define foreign keys. I'm trying to give my Foreign Key column the name I want. Here is an example showing how to create a composite unique key via fluent API. ... Two Foreign Keys in Entity Framework Core. If you want to avoid fluent api (for whatever reason #differentdiscussion) this works fantastically. 75. … Thanks, In these cases there cannot be a foreign key because the dependent's foreign key IS its primary key. Generally, you don't need to configure one-to-one relationships manually because EF Core includes Conventions for One-to-One Relationships. ... How to set ForeignKey column name in fluent API on EF Core. In my case I needed to include an additional foriegnKey annotation on the "Match" entity, because my fields/tables have strings for PK's. Cascade - dependents should be deleted; Restrict - dependents are unaffected; SetNull - the foreign key values in dependent rows should update to NULL In this article. Entity Framework Core. Ask Question Asked 4 years, 1 ... now it's about column name too. The ForeignKey attribute is used to specify which property is the foreign key in a relationship.. So for this: EF Core 5; Articles; Knowledge Base; Online Examples; Navigation property without foreign key, or fluent api version? A key serves as a unique identifier for each entity instance. However, if the key or foreign key properties do not follow the convention, then you can use data annotation attributes or Fluent API to configure a one-to-one relationship between the two entities. The default code first convention for ForeignKey relationship expects foreign key property name match with the primary key property. In EF-core (current version 2.2.1) composite primary keys can't be modeled by data annotations. It throws a run-time exception: Entity type 'Parent' has composite primary key defined with data annotations. This is not possible in my case, since all my tables have a foreign key to it. Is there any way I can set the foreign key in EF Core without having explicitly set the properties on both entities? To set composite primary key, use fluent API. The composite key consists of ProjectId and SectionOdKey. The OnDelete method takes a DeleteBehavior enum as a parameter:. The Entity Framework Core Fluent API OnDelete method is used to specify the action which should take place on a dependent entity in a relationship when the principal is deleted.. String representation of an Enum. The mapping is almost identical: Related. Now without attributes, only fluent api. 2. – Dmitry Oct 27 '16 at 16:06. The Entity Framework Core Fluent API HasAlternateKey method enables you to create an alternate key by placing a unique constraint (and therefore a unique index) on a property or properties other than those that form the primary key. 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