C# entity framework get related entities

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August undefined, 2024

WebThe Load () method executes the SQL query in the database to get the data and fill up the specified reference or collection property in the memory, as shown below. Query () You can also write LINQ-to-Entities queries to … WebIf child objects are not being populated when they are called in Entity Framework with Code First, there are a few things that you can check: Ensure that the child object is included in the query. You can use the Include method to specify which related entities to include in the query:

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WebMar 16, 2024 · public IActionResult getAllProperties () { var properties = db.properties .Include (cat => cat.category) .ThenInclude (sub => sub.subCategory) .ThenInclude (sec => sec.SecondSubCategory) .Include (e => e.heating) .Include (e => e.type) .OrderByDescending (x => x.id) .ToList (); return Ok (properties); } Share Improve this … WebJun 26, 2016 · 4 Answers. One cheap easy way of cloning an entity is to do something like this: var originalEntity = Context.MySet.AsNoTracking () .FirstOrDefault (e => e.Id == 1); Context.MySet.Add (originalEntity); Context.SaveChanges (); the trick here is AsNoTracking () - when you load an entity like this, your context do not know about it and when you ... tahe magic instant mask

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WebOct 12, 2024 · The simplest way to use lazy-loading is by installing the Microsoft.EntityFrameworkCore.Proxies package and enabling it with a call to UseLazyLoadingProxies. For example: EF Core will then enable lazy loading for any navigation property that can be overridden--that is, it must be virtual and on a class that … WebSorted by: 101. The best way to refresh entities in your context is to dispose your context and create a new one. If you really need to refresh some entity and you are using Code First approach with DbContext class, you can use. public static void ReloadEntity ( this DbContext context, TEntity entity) where TEntity : class { context ... WebJul 8, 2016 · You cannot nest calls that way. Include works on the core entity you are working with - that entity defines shape of the query so after you call Include(x => Wheels) you are still working with IQueryable and you cannot call extension method for IQueryable. You must again start with Car: tahe infusion gold a+b

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Web20 hours ago · Each entity in the hierarchy additionally has a foreign key to the entity that is it's parent, as well as a collection of children entities. For example: public class BaseEntity { [Key] [DatabaseGenerated(DatabaseGeneratedOption.Identity)] public Guid Id { get; set; } public DateTime CreatedOn { get; set; } public DateTime LastUpdate { get; set WebMar 11, 2024 · Entity Framework Core uses Language-Integrated Query (LINQ) to query data from the database. LINQ allows you to use C# (or your .NET language of choice) to write strongly typed queries. It uses your derived context and entity classes to reference database objects. EF Core passes a representation of the LINQ query to the database … tahe k2 beachWebApr 15, 2024 · What would be the best way to go about getting a single entity from the db? Using EFC2.1 pre release build. Edit: Also found that if you use … taheke waterfall track

"WebIn Entity Framework, you can use the Include method to eagerly load related entities. However, if you have a hierarchy of related entities and you want to include all of them, … " - C# entity framework get related entities

C# entity framework get related entities

Explicit Loading Related Entities in EF 6 and EF Core

Entity Framework supports three ways to load related data - eager loading, lazy loading and explicit loading. The techniques shown in this topic apply equally to models created with Code First and the EF Designer. Eagerly Loading. Eager loading is the process whereby a query for one type of entity also loads … See more Eager loading is the process whereby a query for one type of entity also loads related entities as part of the query. Eager loading is achieved by use of the Include method. For … See more Even with lazy loading disabled it is still possible to lazily load related entities, but it must be done with an explicit call. To do so you use the Load method on the related entity’s entry. For example: See more Lazy loading is the process whereby an entity or collection of entities is automatically loaded from the database the first time that a property referring to the entity/entities is accessed. When using POCO entity types, … See more Sometimes it is useful to know how many entities are related to another entity in the database without actually incurring the cost of loading all … See more WebYes, the entities that have been generated by EF. It would be interesting to see the definition of the Role property of your User entity. Go to the definition of your property (in Visual Studio, click on the property and press F12) then copy/paste it. Maybe be there is a problem with a navigation property. – ken2k Jan 6, 2012 at 16:14

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WebOct 12, 2024 · In this article. This topic will cover how to add and attach entities to a context and how Entity Framework processes these during SaveChanges. Entity Framework takes care of tracking the state of entities while they are connected to a context, but in disconnected or N-Tier scenarios you can let EF know what state your entities should be in. WebMar 11, 2024 · Entity Framework Core allows you to use the navigation properties in your model to load related entities. There are three common O/RM patterns used to load …

WebNov 29, 2011 · You can use Linq to Entities. You can match every object in entity1 and check if there is a corresponding data/object entity in entity2. using (NorthwindEntities … WebIf you are using Entity Framework 4.1 or later, you can use: var discussion = _repository.GetDiscussionCategory (id); // Count how many messages the discussion has var messageCount = context.Entry (discussion) .Collection (d => d.Messages) .Query () .Count (); Source: http://msdn.microsoft.com/en-US/data/jj574232 Share Improve this …

WebAug 19, 2012 · So when you are unpacking the task you should be able to get the related entity aswell. Things to check: The task entity should have the browse ability to the person entity else this will fail. Add the [Include] keyword on top of the person entities inside the metadata of task in the metadata file in your service layer.

WebOct 28, 2014 · context.Entry (reward).Collection (c => c.Campaigns).Load (); Manually Include () the Campaign property reward = context.Rewards.Include ("Campaigns") .SingleOrDefault (r => r.Id == reward.Id); Although, I'd suggest Load since you already have reward in memory. Check out the Loading Related Objects Section on this msdn doc for …

WebMay 12, 2016 · So adding .ToList() would solve the issue as all entities are then retrieved from the DbContext before the iteration starts. foreach (Entities.Apointment app in apps.ToList()) // added ToList() If you wanted to materialize the list using async you could do. foreach (Entities.Apointment app in (await apps.ToListAsync())) Edit from comments tahe inquiryWebAug 22, 2014 · using (var ctx = new MyContext ()) { ctx.Parents.Attach (parent); ctx.Entry (parent).State = EntityState.Added; // or EntityState.Modified ctx.SaveChanges (); } The first line attaches the parent object and the whole graph of its dependent child objects to the context in Unchanged state. tahe keratin gold satinWeb2 days ago · Furthermore, I've got these entities (only relevant properties are included): ... c#; linq; entity-framework-core; automapper; or ask your own question. The Overflow Blog Going stateless with authorization-as-a-service (Ep. 553) ... Get SQL code from an Entity Framework Core IQueryable 1. Linq, EF Core - group by on one field and use other ... tahel opticWebIn Entity Framework, you can use the Include method to eagerly load related entities. However, if you have a hierarchy of related entities and you want to include all of them, including the related entities for each entity in a collection, you can use the ThenInclude method to chain the Include calls together. Here's an example: twelve knightsWebJun 2, 2024 · But if you need to use stored procedure you will have to add some more code. Change the SP. CREATE PROCEDURE dbo.GetAllParents AS BEGIN SELECT p.ID as ParentId, p.Name as ParentName, c.ID as ChilId, c.Name as ChildName FROM dbo.Parent p INNER JOIN dbo.Child c on c.ID = p.ChildID END. and create a class for a sp result. twelve knltb pasWebJan 12, 2024 · Tracking, no-tracking and identity resolution. Using SQL queries. Asynchronous programming. Additional resources. Querying efficiently is a vast subject, that covers subjects as wide-ranging as indexes, related entity loading strategies, and many others. This section details some common themes for making your queries faster, and … tahe lifestyle soloWebApr 10, 2024 · One of the slower parts of a database query is the transfer of the data to your machine. So it is good practice to transfer only the data you plan to use. When you use LINQ in entity framework, using Queryable.Select is a good way to specify exactly what data you want to transfer. This is usually done just before your final ToList ... twelve krabby patties on wheat buns