WebC# EF upsert是否必须手动完成?,c#,sql,entity-framework,C#,Sql,Entity Framework,我要向上插入现有实体的引用成员 我必须为upsert编写特定的代码吗 意思:我必须检查我是在处理现有的推荐会员还是新的推荐会员 还有其他简单的方法吗 如果只执行保存,会发生什么情况 public void SaveCofiguration(MamConfiguration_V1Ui itemUi ... WebJan 12, 2024 · Simple query and update. Query then insert, update, and delete. Each DbContext instance tracks changes made to entities. These tracked entities in turn drive the changes to the database when SaveChanges is called. This document presents an overview of Entity Framework Core (EF Core) change tracking and how it relates to …
c# - Can I update an attached object using a detached …
WebAug 18, 2024 · The best part of the offline database is that as the database stay visible in SSMS, we can bring it back online very quickly. Detach and attach command is usually helpful when you want to move your database from one location to another location. In most cases, Offline and Detach commands can be executed safely without any data loss. WebDec 3, 2024 · It is easy to check for an unset key when the entity type is known: C#. public static bool IsItNew(Blog blog) => blog.BlogId == 0; However, EF also has a built-in way to do this for any entity type and key type: C#. public static bool IsItNew(DbContext context, object entity) => !context.Entry (entity).IsKeySet; cineworld unlimited price increase
Attaching and Detaching Databases on SQL Server Database …
WebFor each entry in each collection, look it up in the database; If it exists, use the Update() method to update it with the new values; If it doesn't exist, add it to the appropriate DbSet; Return the attached objects and replace the collections in the root object with the collections of the attached objects; Find and update the root object WebI had this issue before with the languages and my solution was to search for the attached language objects, detach them from the context, move their PK to the updated object … WebApr 7, 2024 · The Attach methods are provided to enable you to put entities into a new data context after they have been detached. Even if you are serializing proxy objects in place of the LINQ to SQL entities, you still have to construct an entity on the data access layer (DAL), and attach it to a new System.Data.Linq.DataContext, in order to submit the ... diagnosing which tire sensor is bad