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 want to add recored and immediately after add get id value of that record.
View 1 Repliesthe 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 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?
View 2 RepliesI 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 a one-to-one relationship on two tables with are represented by 2 classes in my EDM. I am trying to save a new record and am confused how to save to the second entity. I have tried the following.
Dim myObject as new MyObject
myObject.prop1 = 5
myObject.prop2 = "Test"
myObject.myOtherObject.prop1 = 3
myObject.myOtherObject.prop2 = "Hello"
But I get an error when I hit myObject.myOtherObject.prop1 = 3 because myOtherObject hasn't been initialized. How do I initialize an child object under myObject?
I have a webservice which of course has to be .net 3.5 (a side note is does anyone know why you can't create a webservice using .net 4.0?).
Anyhow it is using entity framework, which I have recently discovered was a really bad mistake to try to use this in .net 3.5.
I have a table "Licenses" with the following columns: LicenseKey, ProductCode, OrderID, Seq, UserName.
In my asp.net 4.0 application I can simply do the following to perform an update:
[Code]....
But it appears there is no ExecuteStoreCommand in .net 3.5 with entity framework. Can anyone explain to me how to accomplish the same thing? The thing I need to point out is that because this is a multi-user access service. I need to verify that SQL will only update the given record where OrderID and Seq is what I tell it ONLY if the UserName is already null. So if two users process the same statement at the same time only one would work and the other would not because the sql should fail (or return 0, rather than a 1) for the second one.
I set up Entity Framework for my Table and Stored Procedure to return data. Created a Domain Class as well.
In Domain Class, I am returning Objects as collection.
On .Aspnet page when I drop a Control(Combo,Dropdown) I can set up the source for the controls visually if the source is table.
However, In domain class I have stored precedure object that return collection of data And I cant not set up visually from Designer, I am only available to write code behind. is it possibble that i can set up from desingner.
CAN we use Entity framework in web services.I the following error while the code connects to the database using entity framework
View 3 RepliesI have a sql server database that includes the field ArticleID of type uniqueidentifier that is a primary key and is set to be auto-generated by the database when a new article is added.If i generate my entity model and do the following code:
[Code]....
Then a new article is saved to the database but the entity framework must be generating a new blank Guid and saving that to the database rather than allowing it to be auto generated as the articleid that shows up saved is all 0.How can i get the Entity Framework to let the Database generate the ArticleId?
Conseptually what I'm doing is simple, and technically it may even be simple, but I'm still rusty. Here's what I'm trying to do:
I have a webform that allows the user to enter a new record, and in there I have also included a couple FileUpload controls. Upon clicking the "Save" button, I'm saving the details entered into one table (ITEMS), and also inserting the FileUpload details (path, id, upload_user) into another table ATTACHMNTS). Because one ITEM can have many attachments, I needed to split the tables up. So on save, I need to save the ITEM, save the ATTACHMENT, and then also put the ITEM_ID in the ATTACHMENT table. I'm second guessing myself because I think all I'd have to do is after I do the ITEM insert, do a SELECT MAX on the ITEM table and hold the newest (MAX) id in a variable and then use it in the ATTACHMENTS update. I'm not 100% on this because there IS a chance that someone else could save a few milliseconds later and I'll link the wrong ITEM. See my delima?
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.
When I run the code below, it works
int charId = int.Parse(Request.Params["charId"]);
EveFPT ctx = new EveFPT();
var theCharQuery = from a in ctx.tblChars
where a.id == charId
select new
{
Name = a.name,
CorpName = a.tblCorps.name,
AllianceName = a.tblCorps.tblAlliances.name
};
if(theCharQuery.Count() == 1)
{
var theChar = theCharQuery.First();
lblCharName.Text = theChar.Name;
lblCorpName.Text = theChar.CorpName;
lblAllianceName.Text = theChar.AllianceName;
}
However, If I the below
var theCharQuery = from a in ctx.tblChars
where a.id == charId
select a;
if(theCharQuery.Count() == 1)
{
tblChars theChar = theCharQuery.First();
lblCharName.Text = theChar.name;
lblCorpName.Text = theChar.tblCorps.name;
lblAllianceName.Text = theChar.tblCorps.tblAlliances.name;
}
the statement theChar.tblCorps always returns null.
Tables: Article, Author, Comment (1 article and 1 author can have * comments)In the database is 1 article, 1 author and 1 comment.
The problem is, that code
myBD my_bd = new myBD();
var articles = by_bd.Article;
works OK, I can see that an Author and an Article has 1 comment. But that code
var comm = (from u in my_bd.Comment
where ......
select u);
returns the comment but it has NULL values in property Article and Author. Why ?
I have an ASP.NET Page that updates registered User Address Details for a selected record.
Below is the Update method that i am calling from Controller.
When i am calling ApplyPropertyChanges method, I am getting the below error.
Did anyone run into the same error while updating the record with Entity Framework.
[code]...
i joined together more than one entity: Customer, Personel etc. i used inner join structures. if i look adonet entity framework ,5 entities are generated. i need to run this SP in C# side:
[Code]....
LOOK BELOW PİC : you can understand it :
MY C# codes: [Code]....
How can i get all joined data from sql with using randevu.GetRandevular(customerID
I have 3 tables User, role and UserInRole THe entity frame work made entities for User and Role and I have successfully made a join with the user and role entities using user.add(role); but I can't seem to get it to remove the link (I want to retain the user and role just remove their association).
using (ProviderEntities context = new ProviderEntities())
{
User u = context.User
.Where(n => n.ApplicationName == application)
.Where(n => n.Username == username).First();
Roles r = context.Roles
.Where(n => n.ApplicationName == application)
.Where(n => n.RoleName == roleName)
.First();
r.User.Remove(u);
context.SaveChanges();
}
The oposite worked when I did r.User.Add(u); but it wont let me now remove it after it been created. Driving me mad as I can't see where I have gone wrong.
I transfered my data from MDF files to MS SQL Database, but I can't get it working with entity framework.
My Old connection string is:
metadata=res://*/Models.EntityModel.csdl|res://*/Models.EntityModel.ssdl|res://*/Models.EntityModel.msl;provider=System.Data.SqlClient;provider connection string="Data Source=.SQLEXPRESS;AttachDbFilename=|DataDirectory|TripsDB.mdf;Integrated Security=True;User
Instance=True;MultipleActiveResultSets=True"
I put all data from TripsDB.mdf to Trips table in local MS SQL 2008 Enterprise database. Also changed connection string to:
Server=WIESIEK;Database=Trips;Trusted_Connection=True;providerName=System.Data.SqlClient;User ID=Jan J. Roman
But my application throws System.ArgumentExceptio with message: The 'server' keyword is not supported.
on line:
private TripsDBEntities2 _entity = new TripsDBEntities2();where TripsDBEntities2 is Entity Framework instance.
I have a stored procedure that generates a float value. I've added the stored procedure to my edmx file and created a function import, but the function isn't showing up in the object browser or via intellisense.
I'm using Visual Studio 2010 and I've verified that the stored procedure works in SSMS. Here is the current stored proc I'm using:
[Code]....
CarType
Id - PK
Name
CarDetail
Id - PK
TypeId - FK to CarType
I have this simple example here and I want to insert a new CarDetail into the database but for some reason I cannot get the EntityKey to work in EF4 and Framework4 beta 2.
If i declare the following
car_detail.CarTypeReference.EntityKey = new System.Data.EntityKey("MyDB.CarType", "Id", 1)
Each time i try to call SaveChanges, it throws a INSERT constraint error saying that there is a conflict between CarType and CarDetail with the FK. It just seems like the hard coded 1 for CarType is NOT being passed through but instead the default value of 0. What is going on?
If i call car_detail.TypeId = 1 then it works fine with the INSERT.
Why doesn't the EntityKey method work?
how to do this query in EF1:
[Code]....
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);
I have to change the username column in my database to nullable, which means everywhere in my code, I now have to check username.HasValue and change references to username to username.Value. Is there anything I can do to avoid having to change all the references to username to username.Value?
View 1 RepliesI have created a .edmx for the northwind database. When I run the following statement, the correct number of detail records are retrieved and I can access the detail fields, but how do I access the order header record to view OrderDate, ShipAddress, etc...?
[Code]....
public void saveOptionalCourses( ArrayList coursesAdded, int studentID)
{
StudentOptionalCoursesXRef XRefObject = new StudentOptionalCoursesXRef();
using (var EntityObject = new SchoolProjectEntities2())
{
foreach ( string list in coursesAdded)
{
XRefObject.StudentDetails = EntityObject.StudentDetails.Where(c => c.StudentID == studentID).First();
XRefObject.OptionalCourses = EntityObject.OptionalCourses.Where(c => c.OptionalCourseName == list).FirstOrDefault();
EntityObject.AddToStudentOptionalCoursesXRef(XRefObject);
}
EntityObject.SaveChanges();
}
with this above method and could save only last row that am returning remaining rows are iterated but are not saving on to database