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?
Related
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.
I am using Entity Framework (v6.1) with the Database First method. I have created my EDMX file and it references a stored procedure I selected while creating the EDMX via the EF wizard. My question is how do I use what the stored procedure returns?
Below is my dbContext and the name of the stored procedure GetHtmlContent. The stored procedure takes contentId as an integer parameter.
Here is the SQL of the stored procedure GetHtmlContent ..
SELECT
HtmlContent.contentId,
HtmlContent.[Name] AS 'Name',
HtmlContent.HTML AS 'HTML',
HtmlContentCategory.CategoryTitle
FROM HtmlContent
LEFT JOIN HtmlContentCategory ON HtmlContent.CategoryID = HtmlContentCategory.HtmlContentCategoryID
WHERE HtmlContent.ContentId= #ContentId
Below is what I get when I hover over the stored procedure method contained within the dataContext to see what is returned.
System.Data.Entity.Core.Objects.ObjectResults<GetHtmlContent_Result> dbContext.GetHtmlContent(contentId)
This is where I am getting confused ...
Is the <GetHtmlContent_Result> a type representing the dataset returned by the stored procedure?
What is System.Data.Entity.Core.Objects.ObjectResults?
Since I am accepting a collection of records from the stored procedure do I need to create a class to hold the results of the stored procedure?
Is the a type representing the dataset returned by the stored procedure?
GetHtmlContent_Result is representing each record that is produced by stored procedure.
HtmlContent.contentId,
HtmlContent.[Name] AS 'Name',
HtmlContent.HTML AS 'HTML',
HtmlContentCategory.CategoryTitle
What is System.Data.Entity.Core.Objects.ObjectResults?
The ObjectResult is an enumerable collection class, but it is a
forward-only collection so once it has been enumerated, you cannot
enumerate it again. For example, if you call ToList on the result,
e.g., GetDetailsForOrder(3).ToList(), then you cannot subsequently
provoke another enumeration by calling ToList again, binding the
results to a control or executing a foreach over the results. - MSDN
Since I am accepting a collection of records from the stored procedure do I need to create a class to hold the results of the stored procedure?
It's just like other entities that represent tables in the database, a POCO. You can use it directly.
I am using database first in an MVC application, and in certain situations I need to use stored procedures to map data from the database to complex types (and vise versa).
It was easy to setup the mapping to complex types, when reading data from database, but I can't seem to find out, how to map complex types to stored procedures when writing data to the database. It looks like it is only possible to use properties from the underlying entity itself, when choosing the mapping parameters.
I was wondering if it is even possible to use complex types when inserting, updating and deleting data using stored procedures.
Example:
--Database table--
ID int
StartDate varchar(8)
-- Complex type --
ID int
StartDate DateTime
I would like to create an instance of the complex type and insert its data into the database using a stored procedure. The conversion from DateTime -> string would be done in the stored procedure.
Is that possible?
Hi I have a stored procedure which returns result of some fields of multiple tables . can i map the result to associated tables (without using complex types)?
thanks.
Out of the box implementation allows you mapping only to flat structures. So either your stored procedures returns single mapped entity type or you need a complex / custom type. It doesn't allow mapping to relations.
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.