Save parent and child in entity framework. Also noticed the foreign key constraint in the child.
Save parent and child in entity framework 0 Code first with existing database. Dependencies may exist due to foreign key constraints, model requirements, or store-generated values-exception when using a self-referencing relationship in Entity Framework. When I save the modifications on the form I first save the changes to the parent entity and then run the following method to update the corresponding child entities: Mar 31, 2012 · I read quite a number of posts of programmers that run into the Unable to determine a valid ordering for dependent operations. Country = txtCountry. My n-tier database model includes about 30 or so tables, with a number of multi-leveled parent-child relationships throughout. public class Parent { public int Id ( get; set; } public string Name { get; set; } pub Aug 22, 2014 · When I save an entity with entity framework, I naturally assumed it would only try to save the specified entity. In this article, let’s have a look at how related data can be saved and retrieved. Child. Jan 23, 2021 · I have one DB table which is self-referenced to form the parent child relationship. Here’s a step-by-step explanation: Get the existing parent entity from the database using Jun 13, 2010 · I'm using . Customers Jun 29, 2021 · This blog application uses entity framework core code first approach. ID's are all int with auto increment. The article demonstrated how to save entities, but we have not yet saved and retrieved the related data (using foreign key relationships). Name = txtName. Oct 8, 2019 · In my ASP. Actually, storing such a self referencing table with one SaveChanges is not possible, cause the ID of an new entity, is generated, when it is saved. Open() Using transaction As DbTransaction = entity. NET Core 2. Text } entity. How do I force EF to only save the entity I want to save and therefore ignore all child objects? Nov 4, 2016 · My entity relationship is Customer > Address > Contacts. Post and Related Data Aug 8, 2020 · protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder. When we have an entity with child relationships we can add objects directly to their ICollection using Add method. Because the Parent initially does not exist, we can add it by calling the DbContext. Text, . Now when you use remove you get the error Jan 14, 2013 · Im wanting to use Entity Framework POCO in a disconnected (from context) mode. I also checked the parent's primary key when saving the child and it does exists in the database. Everything is working great. Also noticed the foreign key constraint in the child. May 6, 2015 · Parent. Mar 4, 2014 · We have an entity that has child entities of the same type. Modified 7 years, 11 months ago. Reverse engineered the classes with power tools. Sum(p => p. Oct 2, 2017 · The key here is that I'm using conventions to tell EF that there is a parent-child relations. Entry method to track the parent entity’s state and manually handling the child entities. Logs); modelBuilder. . Feb 22, 2015 · We are using Entity Framework Code First with Foreign Key relationships. Entity<Parent>(). Connection. Database has two tables. com We want to update the Parent entity and add, modify, or delete child entities as needed. Childs); modelBuilder. Note that i am using database Nov 26, 2010 · Good afternoon-I am developing a Silverlight application using LINQ to Entity Framework for the data access layer. The data for these properties is pulled from an external source but I want to save th When using the CTP 5 of Entity Framework code-first library (as announced here) I'm trying to create a class that maps to a very simple hierarchy table. The Employee table contains column of most recent ProductSaleId . Can I update the parent entity to get the parent properties along with only the changed child entities within the collection to update. On form submit I have a detached invoice object that has an EntityCollection of modified InvoiceLog Jan 21, 2018 · Use this generic sub to mark the child state, easy to use. This will add the Parent and the list with Child items to the database. Second issue is that because the Status field is not an actual database field, the values are all at the enumerations default value. Entity<Child>(). That is attaching an object that was retrieved by one context to another context, will allow you to save changes to parent objects but not children. Logs); } The idea is for log entries for both Parent and Child be saved also, when Parent and Child is saved. Notes: PromatCon: the entity object; amList: is the child list that you want to add or modify As far as I know EF can save child entities only if the parent object was retrieved with the same Context that is trying to save it. Id Name ParentId 1 A null 2 B 1 3 C 2 4 D 2 5 E 1 I want this table be queried thru EF core and retrieve the Oct 30, 2012 · Entity Framework 5. microsoft. In the code, the Parent is created with the initial list of Child items. Viewed 98 times 0 . NET MVC application using Entity Framework. I've got a Main_User Type, and I have an ASP. However, it is also trying to save that entity's child entities. In my scenario I'm creating a new Parent object and want to attach an existing child object to it and then save it to the db. The child has a ParentId that matches ParentId in its parent. Here's the SQL that builds the table: CREATE Feb 21, 2021 · I have tried all combinations of "add child via the parent's navigation collection, add child via directly adding to DbSet and setting parent FK as object OR integer key" and it only works when I reconfigure the model to destroy all of the relationships between Parent and Child and keep things reduced to weak references. The proposed solution involves using the DbContext. I've added a number of parent records and now want to add child records to specific parents. i am trying to update data in customer table and remove specific data from Address & Contacts tables and try to add again data in Addre Dec 16, 2013 · I'm using EF and WebAPI and trying to save a new object that has many child properties (eg city, country, etc). I created the tables using the entity framework tooling. I have developed 2 models, using the database first (code) approach for a SQL Server 2008 R2 database. Status == New). BeginTransaction() Try Dim customer As Customer = New Customer With { . Add(Parent) method. You have two chances to solve Jul 11, 2014 · I followed this article and created my Entity Framework POCOs via the "Code first from database" model in the Entity Data Model Wizard. NET 4 EF and am trying to save the child entities (InvoiceLogs) of an entity (Invoice). MVC project I have a master-detail form that I use for editing a PARENT table that also has a list of child entities (stored in CHILD table). Where(c => c. We investigating on ways on handling removing objects from an entities ICollection in our application. Update the parent I have a parent entity which has collection of child entities. If I was saving a child normally I would just save a new entity with the parent id set to the id of the parent. This is causing all sorts of integrity problems. This might require further update-Commands, to the entity you just stored. Parents. Where DbContext. Here’s a step-by-step explanation: Get the existing parent entity from the database using Dec 14, 2020 · Adding the parent. In the entity world they are connected through a navigation property of the same type as follows: public class SomeType { public id; . One parent and one child with foreign key back to parent ID. 2. This produced the following two C# classes: This produced the following two C# classes: We want to update the Parent entity and add, modify, or delete child entities as needed. Count()) The first problem is that this goes back to the database once for each parent record and gets all linked child records. One model is essentially a parent mo Feb 20, 2012 · I am practicing with a code-first set of classes with a parent-child relationship between them. Notice how the id names used between the two entities match up. I have a parent entity which contains a list of children. Parents is a DbSet<Parent>. Apr 15, 2014 · The problem is when i do this EF inserts a New Parent and then add the child with a foreign key pointing to new newly inserted parent instead of inserting just the child with mapping to already existing parent. HasMany(a => a. So you first need to save it, and then you get the ID, that you can store in another entity. I have a model that is like follows: public class Parent { public int ParentID { get; set; } public List<Child> Aug 20, 2020 · How do I add a new child record in Entity Framework and update the ParentId reference key? We have an Employee and a ProductSales table. Ask Question Asked 7 years, 11 months ago. public virtual IList<SomeType Feb 2, 2017 · Entity Framework Parent and Child Save. public class Parent { ///parent properties public virtual ICollection<Child1> Children1{ get; set; } public virtual ICollection<Child2> Children2 Sep 9, 2022 · Protected Sub Insert(ByVal sender As Object, ByVal e As EventArgs) Dim entity As AjaxSamplesEntities = New AjaxSamplesEntities() entity. The Solution. May 18, 2021 · I am running Entity Framework Core with a Blazor WASM Hosted Solution. public class Parent { public int Id { get; set; } public List<Child> Children { get; set; } } public class Child { public int Id { get; set; } } EFcore will create a ParentId as a foreign key in the table Child. See full list on learn. iry rgbrod jvki gjuszx hjfkwq vcjqm azqqciea tesq qymmw jar