Generate Enum From Values Present In A Table Using ADO.NET Entity Framework?
Apr 14, 2010My requirement is to create an Enum based on values present in a table from DB. I am using ADO.NET Entity Framework model (.edmx file),
View 2 RepliesMy requirement is to create an Enum based on values present in a table from DB. I am using ADO.NET Entity Framework model (.edmx file),
View 2 RepliesIs it possible to choose a specific database that will be used with the entity framework? At this time, I use the connection string in the Web.Config as database authentication.
I have twelve databases, each of them has the same structure and the same stored procedure.
There is one database for each client. When a client wants to login into the system, he needs to choose his database name from a listbox.
I would like to create a dynamic connection string which will include the database name chosen by the client.
Can I generate entity framework model by clicking button in browser in client-side and save it back to web server PC?
View 2 RepliesI 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.
View 2 RepliesI have a sql server table with a date column that has a default value of GetDate()
this default does not seem to get passed to the EF and so i was wondering what the most elegant way was to code this default value within my asp.net application? I dont want to manually alter the EF Model as i may want to re-import it and dont want to lose these changes.
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?
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 ?
So, have a search form where users can enter one or more keywords, these keywords are then held in a List<string> called keywords. Now using Entity Framework have an Organisation entity with a Name field. What I want to do is select those organisations whose name contains all the keywords. I don't care if they are in the right order or not but it just contain all the keywords. Also organsiations is a big table in the database so I don't want to materialise all the organsiation objects on the server and then loop through them. So what I'm looking for (excuse my LINQ naivety here) is equivalent to the non-existent LINQ statement:
[Code]....
I'm sure this must have already been answered but just can't find it.
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 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?
My setup is this; first I'm defining a couple of new rows.
newCompany = new company
companyInfo = value.company_info,
companyName = value.company_name,
organizationNumber = value.company_orgnr
[code]...
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
I've sucefully created a method to insert values through EF, but i've a question (maybe, a newbie question).
Should i send the values to be inserted as strings to the DAL, and then i create the object there or should i create the object in View Layer and then send him to DAL?
Example 1 (DAL):
[Code]....
Example 1 (View Layer, on a click button for example):
[Code]....
Or should i receive the strings in DAL like this: public bool NoticiasInsert(string tituloPT, string tituloEN, string descricaoPT, string descricaoEN)
Then i create the object cdcModel.noticias and set the fields there with the strings values.
What do you advice me to do? I know that both ways works, but i'm trying to develope with better patterns (i don't know if this is the exacly word, sorry my bad english)
cdcModel.noticias campos = new cdcModel.noticias();
campos.tituloPT = "a";
campos.tituloEN = "b";
campos.descricaoPT = "a";
campos.descricaoEN = "a";
if (DAL.NoticiasInsert(campos)
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 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 have a model:
[Code]....
and in my controller, i have:
[Code]....
and this ViewData contains the information of a type of List<SelectListItem>,which can be used to generate a dropdownlist in the view later on. BUT, now i want to write a function in my controller to generate List<SelectListItem> based on different input enum, what like want to do is like this:
[Code]....
however, there are so many errors.
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 am using Entity framework to model my database (model first) however the table generator is creating tables with plural names. I have looked into the ssdltosql10.tt file. It is generating the table names from Entity set. Any way this can be changed to get the table names from "Entity Name" instead of the "Entity Set Name" so I end up with singular table names.P.S. BTW in Northwind Database the tables are pluralized however in adventure works database the tables are singular. I prefer singular.
View 1 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 am mapping a stored procedure to an entity by right clicking on the entity (in the .edmx) and selecting "Stored Procedure Mapping." This brings you to a Mapping Details - "Name of Entity" Window that allows you to select the insert, update, and delete stored procedures associated with the Entity. It also maps the stored procedure parameter to the Entity "Property" (Column).
I'm gettin an error "error 2042: Parameter Mapping specified is not valid." The cause of the error is fairly obvious, in the Insert stored procedure that has been selected, a 'CHAR' parameter is being mapped to an Int32 Entity Property. I altered the stored procedure parameter to match the entity, I deleted the stored procedure, readded, and reslected it as the Insert function. I also cleaned, validated, updated model from database. No matter what I do, the parameter list in the mapping details doesn't reflect the change to the stored procedure. It's stuck on a char --> int32 mapping, even though it has been changed, like it's buried deep in meta data some where.
I am trying to add a new entity and have to refernce associated data to add it. I cannot load the Referencetables. Giving "The EntityReference could not be loaded because it is not attached to an ObjectContext." How do i complete this task in Entity Framework 3.5
[Code]....
I have a stupid problem with the Entity Framework. I get the following Exception:
[Code]....
I have an entity with a 4 fields representing the primary key. I copy it via serialization (works fine). I set the old entity to not valid (Datefield set to a date in the past, this field is part of the PK) and set the copied entity to DateTime.Now.Date. When I call context.AddObject I get the Exception above. I tried copying the entity via reflection but the entity has 3-4 references. And when copied, I get another Exception before even Adding the entity to the context. I also tried setting newObj.EntityKey = null and reset all the fields neccessary for the PK. I just want a whole copy of an entity with a different primary key (and some other fields changed too) and Create it in the database.