Entity Framework Partial Update

部份欄位更新：
Entity Framework - Update Single Property (Partial Update)
EntityFramework update partial model
Entity Framework validation with partial updates
ASP.NET Web API 2:安全的PATCH方法的三種實作

entry.Property(name).IsModified = false

DbSetMigrationsExtensions.AddOrUpdate 方法
DbSetMigrationsExtensions.cs