Configure Primary Key using Fluent API in Entity Framework Core August 9, 2022 Configuring a Primary Key modelBuilder.Entity<OfficeAssignment>().HasKey(t => t.InstructorID); Configuring a Composite Primary Key modelBuilder.Entity<Department>().HasKey(t => new { t.DepartmentID, t.Name }); References https://docs.microsoft.com/en-us/ef/ef6/modeling/code-first/fluent/types-and-properties#configuring-a-primary-key Related