Im working with EF4 and started mapping my classes manually i have a function in the postgres side which receives 3 parameters (all string),and returns me a list,havent found any example how to do so considering the entity frame work 4,any help?
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Hi I have a project which is quite old. It uses stored procedures which isn't an issue but it does have lots of error prone mapping code in old ADO.net. My main goal is to cut down the mapping more than anything. We have a separate library of I guess POCO/DTO type objects that get mapped to.
Can I map stored procedures to these classes easily. I suppose I could use AutoMapper as the mapping will be exact but I'm wondering if there's an easier way that it does out of the box. The list of complex type doesn't show the imported library's business classes. Cheers.
Instead of using AutoMapper, create a complex return type using "Edit Function Import", which has the exact properties as the stored procedure result.
I have the below scenario. I am using EF 5 Code first, MVC 4 on VS 2010. I am using the Unit of Work and Repository pattern for my project.
I am not sure if this is possible or not. Kindly suggest.
I have a model class representing a database table. In the model class, I have a property that is decorated as [NotMapped]. I have a Stored Proc that returns data, similar to the model class. However, when I get the data in a List from the SP, it does not contain value for the [NotMapped] column (SP returns data for the [NotMapped] column though). This may be logically correct with respect to EF.
All I want to know is, do we have a way to get data populated for the [NotMapped] column. I want to achieve, CRUD using LINQ (excluding R - Read).
I would recommend to create a separate complex type for the stored procedure results. Otherwise sooner or later you will find yourself writing code to distinguish between entities coming from the DbSet or from the stored procedure. When the come from the stored procedure they can't be used in joins, for example. Or checks whether or not the unmapped property is set.
A very dirty approach could be to have two different contexts. With code first it is possible to have different contexts with different mappings to the same types, with and without the column ignored (if you use fluent mapping, not with data annotations). But that only succeeds if you tell EF not to check the database schema, so using migrations is ruled out as well. I would not do it!! For the same reason as I mentioned above. I would hate to have a type with a property that sometimes is and sometimes isn't set.
Using EF3.5 with Visual Studio 2010 (cannot upgrade to EF4 at this point - don't ask!).
Wanting to create a stored procedure that aggregates some fields from some related tables and materialize the result of the stored procedure as a custom "entity". This custom entity would be "read only". I set up the custom entity, the stored procedure, and function import. When I build my Entity project, I get the following:
Error 35 Error 3027:
No mapping specified for the following
EntitySet/AssociationSet -
MyCustomEntitySet
It looks like it wants a table mapping defined for my custom entity, however, I would not have one in this case since it aggregates the data over several tables (and filters out some unneccessary data).
Is it possible to map a custom entity to a stored procedure? Is it possible to do so in a way where the "Update Model From Database" functionality will not break the custom entity or stored proc/function import mapping?
TIA!
We used to get around this by creating a view in the db - the view never actually gets used if you map to stored procedures but it does enable auto-creation of the correct mappings in the entity.
Typically for fairly straight forward procs you can copy/paste the sql to generate the view too - saves some time.
In my ASP.NET MVC 2 project I'm trying to call a stored procedure from EF, the problem is after I followed the directions here (went this route because there's nothing in the model that maps to this stored procedure so I added 2 entities for the 2 stored procedures) I get this error:
GCTModel.msl(3,4) : error 3027: No
mapping specified for the following
EntitySet/AssociationSet -
GalleryAnimalLists, GalleryImages.
Now, since I had to add manual entities to map these SP's to how do I get rid of this error message? And ideas on what I'm doing wrong here, or is this post on his blog just wrong for MVC 2?
I ended up deleting the hand rolled entities I created for the function imports and created 2 complex types and mapped the function imports to those and it works perfectly. Just thought I'd share the solution I came up with in case someone came along with a similar issue
This question is an extension of another question, but I think it warrants its own thread. See See Silverlight Question
I have a stored procedure (SQL 2005) that returns a dynamic data set (different columns/schema) each time it is called.
I want to consume this in Silverlight 3.0 so I need to somehow wire this up using Entity Framework and RIA Services. I also need this to be Bindable (Silverlight Grid) so I need these dynamic columns to be accessible via properties (grid limitation). Any ideas?
In the currently shipping version of the Entity Framework, the only type of stored procedures you can map are those which return entity types. The mapping is done, generally, before you compile, although it seems at least theoretically possible to generate Entity Framework metadata at runtime.
Therefore, I see a few choices.
Give up on the whole idea of consuming a procedure which does not return a defined schema. You will never be able to map such a procedure before you compile.
Dynamically generate EDMX at runtime in order to map an entity type to the expected output columns of the procedure before you invoke. Note that the current version of the Entity Framework is a bit finicky about the columns a procedure returns; you can find documentation about this on MSDN.
In .NET 4.0, there are new features which allow you to inform the Entity Framework about your client schema at runtime without having to generate EDMX first. You might be able to leverage these features in order to map some entity type to the expected output columns of the procedure.
Again, in .NET 4.0, there may be support for procs which return scalar values. I can't remember if this is the case or not.
You can always get a standard database connection from the entity connection and execute the procedure directly, using regular SqlCommands. Unfortunately, this makes your code database-provider-specific, but it may be the simplest solution to your problem. Indeed, using such a procedure at all is already database-server-specific.
You might use a WCF web service wraper for accesing your SP and use the WCF service as data source Brad Abrams has a way to do that on his series of articles on RIA Services