tags:

views:

34

answers:

1
Q: 

stored procedure mapping Entity Framework

Hi,

We're using a Function Import in an EF4 model to populate an existing entity in our Model. The entity in the model has a Key field of Id which we're struggling to map as our stored procedure doesn't return an Id field. I've tried setting the value in the mapping to a literal value of 0 but that fails with an EntityCommandExecutionException and the following exception text.

The data reader is incompatible with the specified 'Candidate'. A member of the type, 'Id', does not have a corresponding column in the data reader with the same name.

Short of modifying the stored procedure to return a dummy Id field can anyone recommend what the best approach is for this as the dummy field option feels very clunky to me.

Many Thanks

A: 

If you can't return enough data to fully materialize the entity -- and the Id field is certainly going to be required for that -- then you need to change the return type on the proc to be a complex type instead of an entity.

Craig Stuntz  2010-07-09 12:58:18
Thanks for the response Craig. What we're essentially trying to do is add a Candidate to the Context just from a different DB table so by mapping directly to the stored proc and function import it saves us having to map from the complex type returned by the function to the Candidate entity in code.If that's what we have to do then that's OK but it seems strange that the EF will allow me to bind to the Candidate entity when it knows the return schema of the sp and therefore knows its never going to work out against the Candidate. This is what led me to believe we're missing something.
Daz Lewis  2010-07-09 19:00:20

related questions

NHibernate many-to-one mappings updating unchanged table
nHibernate mapping to custom types
Mapping Oracle bool fields with nHibernate
Color mapping a texture in opengl
Google Maps API - GMarker.openInfoWindowHtml() stopped working
Mapping multiple Values to a Value Object in NHibernate
Getting String Sets into Presentation Layer
Which map api would best support fictionally defined maps?
Mapstraction as a library to access Google maps
Object-relational mapping: What's the best way to implement getters?
What is the ideal data type to use when storing latitude / longitudes in a MySQL database?
Annotated Spring-MVC controller not recognized when controller extends interface
Why isn't my NHibernate bag collection setting the 'parent id' of the children dynamically?
GIS/Mapping solutions that provide easy access to routing data
TIGER shapefiles - using and interpreting
Does such a procedure exist in a Scheme standard and if yes, how is it called?
We're manually mapping our internal data elements to external vendors' xml schema. there's gotta be a better way...
Which tool do I use if I want to map a programming framework visually and see the relationship between all entities?
Why does Python's iter() on a mapping return iterkeys() instead of iteritems()?
Finding City and Zip Code for a Location
How do I calculate distance between two latitude longitude points?
Java code for WGS84 to Google map position and back
Map Routing, a la Google Maps?
Mapping latitude/longitude to a distorted map
Decent, simple, GIS/mapping component for ASP.NET?