How to use Entity framework to pass Table Valued parameter to Stored procedure - entity-framework

I have tables with 2 level hierarchy, Parent->Child->GrandChild
I have create stored procedure with three table valued input parameter ParentTable, ChildTable, GrandChild Table.
Now, I want to consume it in .net using entity framework.
Solution all over internet is, create DataTable in .net , store data in it and pass the same as parameter in stored procedure.
But, I want to use entities instead of data table as data is stored in entity objects. Please suggest. Many Thanks.

You need to have look at this question
Create data table from entities and then pass it to the stored procedure. I haven't tried the code, just showing you the path to go. I hope it may help, looking for better solution.

Related

Call Stored Procedure from Entity Framework that returns compound object

I have a database first setup in .net6
I need to call a stored proc (Lets say it is called GetMyData)
The stored proc is going to return 5 columns from various tables and so does not map to a current entity model.
The only things I can find is to use the context model to return a stored proc result but that will not work as the result set does not map to an existing model. Or a convoluted ADO.Net style call that looks horrific and needs lots of code.
Is there a simple way to call a stored proc that returns various columns from many tables?

If I use EF Code First then how can I add another column to a table?

I created POCO classes and then EF created the database tables for me when I tried to access the data. This worked without problem. I have now populated my tables with data. Not just seed data but real data.
Now I would like to add another column to a table. I assume the first thing I need to do is to add a field to the POCO class but what's next after that? I now have my database filled with data. On the SQL side I know how to add the column myself but do I have to do something with EF or will it automatically pick up that my column was added to the table and my field to the POCO class?
You can use Code First Migrations (http://msdn.microsoft.com/en-us/library/hh770484(v=vs.103).aspx). It can update your database automatically or not.

Entity Framework Inheritance

I'm new to EF, and trying to work out the best way to do something
I have a procedure that returns the details of a table, but also a calculated value. What I'd like is for it to return this information to an entity that could contain this, whether it's the original entity, or an entity that's based on the original (so that if the original table changes, it will still map). What I'd like to avoid is maintaining 2 entities - 1 for the table, and 1 for the stored procedure results.
Thanks...
You could create a view that contained the table fields as well as the calculated values.

Using Stored Procedure to populate dropdown box using Entity Framework

I am using MS Entity Model to attach to my db, and everything has worked fine. But I have a stored proc that returns a list that has two columns (one int and one text column) and I am trying to bind to a dropdownbox. The examples seem to show returning a single column or returning a data type of one of the tables. But my stored proc returns the values from various tables. Can someone point me in the right direction.
Thanks
In EF v1 you can only map a stored proc to an entity type.
In EF v4 you can map a stored proc to an entity type or a complex type.
So the solution will vary depending on which version of EF you use.
If you are using MVC once u have list bind it to the view using SelectList
some thing like this
<%: Html.DropDownListFor( c => c.Movie.LanguageId,
new SelectList((IEnumerable)Model.LanguageList, "LanguageId", "Name", null))%>

Entity framework function import, can't load relations for functions that return entity types

I've created a function import that returns the results of a stored proceedure as one of my entities. however I can't seem to traverse my through navigation properties to access the data in other entities. I know that you can use include() for objectQueries but can't find anything that will force the EF to load my relations for entity results of function imports.
Any ideas??
Thanks in advance.
This is not possible in EF 1.0
The reason is that EF will consider stored procedure values to be just values and not navigation properites.
For example, Employee entity has multiple Order entities. In Order you have a property called EmployeeID. When the database fills your query using include statements, it creates 1 projection query in SQL to populate all of the Order data that a particular Employee could have.
So if I said
var employee = context.Employees.Include("Orders").Where(e => e.ID == 1).First();
var orders = employee.Orders;
The SQL for the first query will create a projection query which will contain orders where the EmployeeID = 1.
Now when your stored procedure runs, this can do any code behind the scenes (in otherwords it can return any set of data). So when SQL runs the stored procedure, it just runs the code in that stored procedure and does not have any knowledge that EmployeeID on Order is an FK to that property. Additionally, if your stored procedure returns an Employee entity, then you are looking at another scenario where you will not even have an OrderID to pursue.
To work around this though, you can setup your query in EF using Include statements that can mirror any stored procedure. If you use the proper mix of .Select and .Include statements you should be able to do the same thing.