I ahve two tables each with a primary key. There is a lookup table in between the two tables with relationships. Below is a simplified look at the table structure
Table 'Product'
Column ProductPK int (Primary Key)
Table 'County'
Column CountyID int (primary key)
Table Product_County_Lookup
Column ProductPK int (Joint Primary Key)
Column CountyID int (joint primary key)
I already have the ProductPK and CountyID. What is the correct LINQ statement to insert into Product_County_Lookup table ONLY?
i'm trying to use Entity Framework to insert into SQL SERVER 2005, using Visual studio 2008.the following codes are a Button onclick event,I want to insert into DB multiple rows at a time
[Code]....
however this does not work, it seems we can only insert into DB only one row at a time
I have three table like above, table C is mapping table which has foreign key of Table A and B.How can i select and insert data in Table C using Entity Frame Work?
I get an cast exception when i am trying to insert an entity in Entity Framework (using code-first). From this code :
public virtual T Insert(T entity) { return Context.Set<T>().Add(entity); }
The cast exception is like "impossible to cast ...Collection'1(Entity) to type (Entity)" I can't figure out why. I am pretty sure ive done everything right. Post entity
public class Post { public long PostId { get; private set; } public DateTime date { get; set; } [Required] public string Subject { get; set; } public User User { get; set; } public Category Category { get; set; } [Required] public string Body { get; set; } public virtual ICollection<Tag> Tags { get; private set; } public Post() { Category = new Category(); if (Tags == null) Tags = new Collection<Tag>(); }................................
I have 3 tables in the database, with a Many to Many relationship:
Assessment(assessID, userID, A, B, C)Grade(gradeID, scoreA, scoreB, scoreC)AssessmentGrade(assessID, gradeID) [PK and FK]I can already Insert into the Assessment AND Grade tables without any problems.I cannot seem to figure out how to Insert into the AssessmentGrade table. There is no separate Entity, because there is only the PK/FK in the AssessmentGrade. I have looked at some tutorials, but none of them seem to address my situation.
I m try to insert record to table, its working well without foreignkey using Entity model. But i need to insert foreign key. I used the following query, its not working well via Entity model.
objFacility.FacilityCategoryReference.EntityKey = new System.Data.EntityKey("testEntities.test", "id", 10);
the problem is that it will insert a new record in a mysql table, I have already done the mapping of the mysql db and I have already done tests returning data and everything works. Now I read from a file, where there are queries written, I have them run me back and the result of true or false based on the final outcome of single query written to the file. Txt; I did this:
using (var w = new demotestEntities ()) ( foreach (var l listaqueri) ( var p = we.CreateQuery <category> (l); we.SaveChanges (); result = true; ) )
but it does not work, I sense that it returns no errors, but neither the result given written in the query. txt file is as follows: INSERT INTO category (id, name) VALUES (null, 'test2')
I'm trying to use formview in order to do insert of a new entity object (called Customer) Customer has a reference to another entity called Address. How can I fill both of them in the same formview?
i'm trying to use Entity Framework to insert into SQL SERVER 2005, using Visual studio 2008.the following codes are a Button onclick event,I want to insert into DB multiple rows at a time
[Code]....
however this does not work, it seems we can only insert into DB only one row at a time
I'm using the linq to entity command to perform a record update. I want to set one of the fields back to NULL but I'm not sure how do it. I have a query such as
Dim record = From r in db.LISTS where r.ID = refID Select r record.Title = txtTitle.text if txtDetail.text = "" then record.Detail = end if
I am busy developing an application using EF4 and MVC2. My development database has a few extra fields that is not in my production database. I have removed the fields from the Model, and published my application to my web server. But now I am getting errors that says I have some invalid column names, but I have removed it from my model. If I go to my Mapping Details, I see the fields removed from the Model are still there, but not mapped to anything.
On my DetailsView for inserting, I have a field "manager code". When the user types in the code, I want another field "manager name" to be populated based on a lookup table in the database. I have done this on a FormView using code behind and "ontextchanged". How can I do this in DetailsView?
I been looking but I cant find any info on this topic Anyway I got a model that looks like this.
[Code]....
I want to cascade delete a category with all its sub categories but I cant make that reference in the database, not with the option to cascade update or delete. It work fine with pagecontents and all the other I got its just this same table reference. In NHibernate I do the cascade setting hbm or with a better way using the fluent option. How do I go about this task now?
i have the following code where I want to retreive the data form a table using entity framework and put it to a list of the same type:
List<ItemDetail> iDets = new List<ItemDetail>();
iDets = (List<ItemDetail>) from l in db.ItemDetails where l.ItemID == varItemID select l;
when I run the page, it throws the following error:
Unable to cast object of type 'System.Data.Objects.ObjectQuery`1[LIBRIModel.ItemDetail]' to type 'System.Collections.Generic.List`1[LIBRIModel.ItemDetail]'.
why i'm having this problem? or am I missing something here if i'm not wrong it worked once, but now it throws this error
Is there a way to export a EF 4.0 Data Model to EF 3.5?
I looked around and found that we are not able to access EF 4.0 from a ASP.Net 3.5 project here: [URL]
Our project is the 1st to go to .Net 4.0 using Entity Framework and we (the team) were wondering if there was a way for the other projects that "might" need to access our data that are still using the .Net 3.5 framework.
Using a very run-of-the-mill database, with identity int for primary keys, a Dynamic Data Entities Project (EntityFramework) displays the primary key for view and edit. When using Linq to Sql, the primary key fields are not displayed.
I would like to hide the primary keys and use Entity Framework (VS 2008, .Net 3.5 sp1).
I'm working on a new project where I have the luxury of working from a Model to Database approach using Entity Framework 4.
The project I'm working on is taking an agile approach where different phases will be rolled out over time.
Will the Model First approach work in my case? I noticed when you "Generate Database from Model" it recreates the entire schema from scratch which will obviously wipe all the data that is in the db. I was hoping for a more "Update Database from Model" approach where the db would just be altered to reflect the changes rather than recreated
I am working with entity frame work to insert data into data base for that I write a web method and query function but data can’t insert data base following my function and web method.
///////////////////////// function AddGridviewData() { var AddRow = new Array(); $('[id*=Test_gridview]').find('tr:has(td)').each(function () { var NewRow = {}; NewRow. name = $(this).find("td:eq(1)").html();
[Code] ...
There are no error and no insert the data into data base.
I am new to entity framework , it is really very good , but I want to know what is the difference between using entity framework with stored procedure or without stored procedure , which one the faster and what is the benefits for using stored procedures with entity framework.
I have an EDM, it includes the entities extension and history. My goal is to use history to keep track of all the changes made to extension entity. For example, if extension with ID 223 has its property 'Name_Display' changed - I want the history entity to record this.
I'm using ASP.NET with VB.NET. Where in my code do I put the hook to say, "update the history entity" and what should that hook look like?