How to convert datatable into Entity Framework classes? - c#

I'd like to run a stored procedure (for performance issues I preferred stored procedures) and at the end I'd like to have module like the one below.
Do you also think in order to achieve this stored procedure is a better solution?
And, if I use a stored procedure, I'd like to preserve my EF structure. So, I probably need to convert the DataTable from the stored procedure into the EF class structure.
Does .NET have some sort of method that handles this conversion or do I have to build up something myself?
And once again, do you really think to do this with a stored procedure is better approach than getting the data over EF, and develop some algorithm on ASP.NET C# to make it look like the one on the picture I uploaded? And if you could also provide WHY, that would be really awesome.
Thank you very much

Why do you want to convert a DataTable to an EF entity? You don't have to use a DataTable to get the results from a stored procedure, you can retrieve EF objects directly from stored procedures
Have a look at this article
Stored Procedures in the Entity Framework

Related

call a stored procedure multiple select query in entity framework code first and then map it to model

I am working on a project using entity framework code first approach, I have a situation where I need to call a stored procedure which returns multiple table, hence I want to map the result to my model. please tell me if its possible to do it and if yes then how can i do it.
Code First currently only supports mapping to tables. This unfortunately means
that you can’t map Code First directly to stored procedures, views, or other database
objects. If you are letting Code First generate a database, there is no way to
create these artifacts in the database, other than manually adding them once Code
First has created the database. If you are mapping to an existing database, there
are some techniques you can use to get data from non-table database artifacts.
i am also facing the same problem and not able to get any solution, so i called stored procedure using ExecuteReader and then mapped it to models using autoMapper.
Let me know if you are looking for code

Entity Framework: Call a stored procedure without mapping

Is there a way to use stored procedures without using the Entity Framework function mapping, which is great but is a complete load of rubbish when any changes are added to the stored procedure, I am aware you can refresh the stored procedure mapping but it's just not efficient. Most of the time when you update your mappings it does not pick up the changes which is extremely annoying.
so far I have tried the following:
var List = db.ExecuteStoreQuery<Business_Voucher_Top5_Result1>("exec usp_BusinessVoucher_Top5");
this works great but can I do it without creating the mapping and pass parameters to it?
Thanks
You don't need to create mapping for ExecuteStoreQuery - you just need to use a type which has properties with same names as columns in the result set.

Entity Framework Function Import when a Stored Procedure has two Result Sets

I have a stored procedure that our DBA wrote and I would like to map it to a function import in Entity Framework. This stored procedure returns two result sets. How is this handled in EF? Will I need to make the DBA write two stored procedures, one for each result set? Or is EF capable of handling this scenario?
Thanks in advance!
Doesn't work out of the box afaik, but have a look at the ADO.NET Entity Framework Extensions

Manually Link Stored Procedure To LINQ

I have a Stored Procedure that returns a dynamic result set based on a temporary table. My project uses LINQ for Data Access, but I can't incorporate LINQ with this Stored Procedure because it has a dynamic "shape" (I can't say before hand which columns will come back or how many there will be), so LINQ can't generate at design time an object that can hold the results.
I am trying to integrate the stored procedure the old fashioned was, using SQLDataAdapter and such, but I was hoping that I could still tie into LINQ so that I don't need to manage a separate transaction mechanism as that would be a disaster.
Is this possible? Thanks.
One best practice is that a stored procedure should never be coded such that it gives different columns in a result set based on inputs.
It sounds like your design is causing the single stored proc to try and do too many things. I'd highly suggest you change this.
First - you aren't using "LINQ" for data access. My guess is you are using Entity Framework for data access. If you are, it depends on which version of EF you are using.
New in Entity Framework 4 is shaping data from a stored proc. For step-by-step instructions, see this blog post: http://blogs.msdn.com/b/nihitk/archive/2010/04/23/ado-net-entity-designer-in-vs-2010-stored-procedure-return-type-shape-sensing.aspx
If you are using Entity Framework 1, which comes with .NET 3.5, then no EF does not have the ability to sense the shape of the stored proc data.

Calling stored procedures

I have a c# application that interfaces with the database only through stored procedures. I have tried various techniques for calling stored procedures. At the root is the SqlCommand class, however I would like to achieve several things:
make the interface between c# and sql smoother, so that procedure calls look more like c# function calls
have an easy way to determine whether a given stored procedure is called anywhere in code.
make the creation of a procedure call quick and easy.
I have explored various avenues. In one, I had a project that with its namespace structure mirrored the name structure of stored procedures, that way I could generate the name of the stored procedure from the name of the class, and I could tell whether a given stored procedure was in use by fining it in the namespace tree. What are some other experiences?
You should try LINQ to SQL.
When stored procedures are the interface to the database, I tend to wrap them in classes which reflect the problem domain, so that most of the application code is using these objects and not calling stored procedures, and not even knowing about the stored procedures or the database connection. The application objects, typically play amongst themselves.
I think it's a mistake to mirror the SPs in your application, as, typically, your relational model is not 1-1 with your application domain object model.
For example, typically I do not have application objects which represent link tables or other artifacts of database design and normalization. Those are collections of objects either contained in or returned by other objects.
A lot is made of the impedance mismatch, but I think it's horses for courses - let databases do what they are good at and OO models do what they are good at.
Have you looked into using the Enterprise Library from MS? It allows you to easily call stored procedures. I generally setup a class per database that is only for calling these stored procs. You can then have something similar to this (sorry it's vb.net and not c#):
Public Shared Function GetOrg(ByVal OrgID As Integer) As System.Data.DataSet
Return db.ExecuteDataSet("dbo.cp_GetOrg", OrgID)
End Function
Where db is defined as:
Dim db As Microsoft.Practices.EnterpriseLibrary.Data.Database = DatabaseFactory.CreateDatabase()
You then have this one function that is used to call the stored procedure. You can then search your code for this one function.
When building my current product, one of the tools that I very much wanted to implement was a database class (like DatabaseFactory - only I didn't care for that one) that would simplify my development and remove some of the "gotchas." Within that class, I wanted to be able to call stored procedures as true C# functions using a function-to-sproc mapping like this:
public int Call_MySproc(int paramOne, bool paramTwo, ref int outputParam)
{
...parameter handling and sproc call here
}
The biggest issue you face when trying to do this, however, lies in the work needed to create C# functions that implement the sproc calls. Fortunately, it is easy to create a code generator to do this in T-SQL. I started with one created originally by Paul McKenzie and then modified it in various ways to generate C# code as I wanted it.
You can either Google Paul McKenzie and look for his original code generator or, if you'd like to write to me at mark -at- BSDIWeb.com, I'll bundle up the source for my SQL class library and the associated sproc code generator and place it on our web site. If I get a request or two, I'll post it and then come back and edit this response to point others to the source as well.
the simplest solution for what you want [and i'm not saying that it is better or worse than the other solutions] is to create a dataset and drag the stored procedures from the server explorer onto the dataset designer surface. This will create methods in the adapter that you can call and check for references.
Although they aren't very fashionable, we use Typed DataSets as a front-end to all of our stored procedures.
Microsoft's new Entity Framework provides just what you're asking for. EF is normally used to create proxy classes for database objects, but one thing a lot of people don't realize is that it also creates proxy methods for stored procedures (auto-generated, of course). This allows you to use your SPs just as though they were regular method calls.
Check it out!

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