I have 2 tables Departments {ID, DeptCode (PK), SubDeptCode (PK)} and Employee {ID, Name (PK), DeptID (PK & FK to ID in Deparments)}.
Both ID fields are declare as UNIQUE and incremental identity. It works fine in sql server 2000 but EF won't map the relation in my app.
1 - Is it necessary to have foreign key to obtain a Relation in Entity Framework between each entity.?
2 - I have a Language Table and many many table with a foreign key related to the language table. Is it right to add this foreign key or I should do something else ?
Ex:
Language
LangID
LangName
TableTextA
TblAID
TextInfo
LangID
TableTextB
TblBID
TextInfo
LangID
TableTextC
TblCID
TextInfo
LangID
etc ...
I just installed Visual Studio 2010 on my Windows 7 laptop in order to start learning the Entity Framework. For some reason that I haven't been able to figure out, when I try to add a new item, there is no template for the ADO.NET Entity Framework. Why the template doesn't exist and what I need to do in order to get the template? I came across a post that stated that in order restore the template that I needed to do the following:
devenv /installvstemplates
I want to use entity framework model for visual studio 2010. I am using oracle database. i was wondering
if it is possible to use entity framework for oracle. If it is not possible then I will just use simple ADO.net and call stord proc and packages.I already downloaded oracle data provider for entity frameowrk from codeplex web site.can someone give me any example that connects to a sample oracle database and use LINQ to oracle
How do I obtain and install the ADO.net entity frame work for VS 2010 ?
Was something missed when VS 2010 was installed ?
I'm trying to use the Entity Framework with a Firebird database in Visual Studio 2010
Useful info:
Windows 7 64-bit
Visual Studio 2010 Ultimate
Firebird 2.5.0
Firebird .Net Data Provider 2.6
DDEX 2.0.5
I've done:
Installed Firebird server (and it works and I can connect to a database) Downloaded DDEX (I've run the registry files) used the gacutil on the FirebirdSql.Data.FirebirdClient.dll and checked that it indeed was installed and it was Modyfied the machine.config for both 2.0 and 4.0 in 32-bit and 64 bit folders to include the provider in the element When I try to add a connection in the server explorer I choose "Firebird Data Source" and the Firebird data provider and press continue. I the "Add Connection" dialog window I fill in the info "data source, database, user, password.." and press ok and then I get the following error:
Failed to find or load the registered .Net Framework Data Provider Also when I try to add a new Entity Data Model I cannot see the Firebird option.. I can only see SQL options. I really need help on this one as I've spent many hours on this and I cannot get it to work.. I've also read other related questions on SO,
How do I upgrade an existing VS2010 ASP.Net 3.5 project from Entity Framework 3.5 to Entity Framework 4.0?
Do I:
- Change the references?
- Change the target framework?
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);
How can I give set foreign key value field in Entity Framework. I have Kartlar entity (related from kartlar table). I need simple save method this field but, RehberID, KAmpanyaId,BirimID is foregin Key....
public static class SatisServicesUpdateTables
{
public static void SaveKartlar(int RehberID, int KampanyaID, int BrimID)
{
using (GenSatisModuleEntities genSatisKampanyaCtx = new GenSatisModuleEntities())
{
Kartlar kartlar = new Kartlar();
kartlar.RehberReference.EntityKey = new System.Data.EntityKey("genSatisKampanyaCtx.Rehber", "ID", RehberID);
kartlar.KampanyaReference.EntityKey = new System.Data.EntityKey("genSatisKampanyaCtx.Kampanya", "ID", KampanyaID);
kartlar.BirimReference.EntityKey = new System.Data.EntityKey("genSatisKampanyaCtx.Birim", "ID", BrimID);
kartlar.Notlar = "hfhfhfhfhfhfghfghfgfghk";
genSatisKampanyaCtx.AddToKartlar(kartlar);
genSatisKampanyaCtx.SaveChanges();
}
}
}
But it throws to me : ArgumentException was unhandled by user code link text
how to handle foreign keys with Entity Framework, when editing or adding a new record. For example, I have a person table, which has a timezone_id linking to my timezone table.
But the model seems to not include timezone_id. I see it's a new way of doing things, but ... how do I store my record?
My method:
[code]...
I can't do u.timezone_id = timezoneid;
I only have u.timezone (which seems to be the actual entity), and u.timezoneReference, which I am not sure what to do with.
I developed and entity framework (.edmx) application in 4.0 in that i got all the data of my querying table and its foreign key referenced tables data also. but when i change my project to 3.5 i am unable to get the data of foreign key referenced tables data.
View 2 RepliesAdding data into kartlar table (RehberID,KampanyaID,BrimID) is ok. But which Kart'ID created? I need to learn which Id created after adding data (RehberID,KampanyaID,BrimID) into Kartlar?
[code]...
How can I do that? I want to get data from Kartlar which data I added?
I have a gridview displaying "registrationtype id" (FK) from the registration table. I want it to display the related name instead of the id from the registartiontype table.
View 1 RepliesI'm trying to insert a new EF object containing a reference to a related table via foreign key, and cannot get the reference stored in the new object. I have two tables in a SQL Server 2008 Database:
Component Templates
PartGroups
with a Foreign Key linking them thus: ComponentTemplates:ID [0..1<->*] PartGroups:ComponentTemplateID
I have imported these tables into a .NET web application project .edmx file (using a new ADO.NET Entity Data Model), and then created a Data Service which I then reference in a Silverlight 3.0 project. The objects are available as expected in the data context called by my Silverlight app and load correctly. Now, when I try to save a reference of ComponentTemplate into a newly created PartGroup, the PartGroup object is created in the database, but the value of ComponentTemplateID in the newly created table record is NULL.
[Code]....
(Note that _ctCtrl.ComponentTemplate is a confirmed non-NULL object reference to the parent object on which PartGroup is a child)
I've created a new ASP.NET website. I've generated an Entity Data Model from my database and have dropped a entitydatasource and gridview onto my page and wired up the gridview to pull from the entitydatasource. Now I get columns like this: id extension prefix did_flag len ten_id restriction_class_id sfc_id name_display building_id floor room phone_id department_id
In each case where the item is named something_id this reflects a foreign key relationship in the database - and I did choose to have the EDM expose foreign key relationships. I'd like to make it so the gridview pulls in the values for these foreign keys rather than just showing the ID numbers - so, for example, department_id might have a value of "101" right now but it should pull from the department table "Marketing".
Does ADO.Net Entity Framework 3.5 support Composite Foreign key/Composite primary key?
View 5 Repliesi'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
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.
This is my UserRoleList.aspx.cs Code where i am passing the session variable to the page Default.aspx.cs..
And the error is: Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints. I have gone through many pages , and tried by making the AllowDbNull property making True and then different things.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
[code]...
This is the code of the second page Default.aspx.cs where i have to user the session varaible to pass in the SQL fucntion named GetDataByUserId as shown below:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
[Code] ....
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.
View 1 RepliesI 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?
I have installed Visual studio 2008 sp1!but only. work3.5 net frame, then I reinstalled. framework3.5 net but failed.and I can not install.OS: Windows 7 Professional information before installingand while installing
I had click Online readme and and found this forum
I have installed VS 2008. but i am not seeing .edmx file in asp.net template.
how to add entity data model page.
I have a solution of VS2008 with 60 odd porject with targetted framework 2.0.
Now I wanted to Upgrade all proejct framework at once from .net 2.0 to 3.5 in and exhisting VS2008 solution
I don't wanted to upgrade each project one by one.
How can i do it
I would like to upgrade my project under .net 2.0 vs 4.0, but on the dropdown list I don't have the 4.0. Only 2/3 & 3.5.
My .Net 4 is full installed with Visual Studio 2010.
why I don't select the framework 4?