Solved

How to do a join with Lync and Entity Framework v4.0

Posted on 2015-02-08
3
52 Views
Last Modified: 2016-06-23
I have a sql server database from which I have created an edmx file in my csharp project. The database has all the requisite foreign keys setup and I can see these as NavigationProperties in the XML view of the edmx. All tables have come through as entities correctly.

In SQL I can run a query as follows:

SELECT * FROM Card.CardRequest cr
  JOIN product.CompanyProductDesign cpd ON cpd.CompanyProductDesignID = cr.CompanyProductDesignID
  JOIN product.ProductDesignCOntent pdc ON cpd.CompanyProductDesignID = pdc.CompanyProductDesignID

which will return only the rows that have been matched from all tables (in my case 6 rows). However I am struggling to get the same result using EF and Lync.

I have got the following code in my c# program:

                using (PrepayEntities ent = new PrepayEntities())
                {
                    cardRequests = ent.CardRequest
                                 .Include("CompanyProductDesign.ProductDesignContent")
                                 .Where
                                    (
                                        cr =>
                                            cr.CRIFileCreated == true
                                            &&
                                            cr.CreationEmailSent == false
                                    )
                                .ToList();
                }

which I know includes an extra Where condition but in any case returns all the rows (in my case 6100 rows). I have tried every possibility from examples that I have found the Internet but just can't seem to crack it - I either get 6100 rows or none.

Please can someone point me in the right direction for what I am sure is a simple solution

Thanks
Phil
0
Comment
Question by:LionCalledAlbert
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
3 Comments
 
LVL 36

Accepted Solution

by:
Miguel Oz earned 250 total points
ID: 40597561
Your LINQ join query should look like:
var result = from cr in ent.CardRequest
join cpd in ent.CompanyProductDesign on cr.CompanyProductDesignID equals cpd.CompanyProductDesignID
join pdc in ent.ProductDesignCOntent on cpd.CompanyProductDesignID equals pdc.CompanyProductDesignID
select new
{
//add more fields as needed
cr.CRIFileCreated,
cr.CreationEmailSent
};

Open in new window


There are more examples using join in this link
0
 
LVL 63

Assisted Solution

by:Fernando Soto
Fernando Soto earned 250 total points
ID: 40597566
Hi Phil;

Try this code snippet to see if it gives you what you are looking for.

using (PrepayEntities ent = new PrepayEntities())
{
    cardRequests = ent.CardRequest.
                   Join( CompanyProductDesign, 
                         cr => cr.CompanyProductDesignID,
                         cpd => cpd.CompanyProductDesignID,
                         (cr, cpd) => new
                             {
                              cr = cr,
                              cpd = cpd
                             }
                   ).
                   Join( ProductDesignCOntent,
                         temp => temp.cpd.CompanyProductDesignID,
                         pdc => pdc.CompanyProductDesignID,
                         (temp, pdc) => new
                             {
                               cr = temp.cr,
                               cpd = temp.cpd,
                               pdc = pdc
                             }
                   ).ToList();
}                   

Open in new window

0

Featured Post

PeopleSoft Has Never Been Easier

PeopleSoft Adoption Made Smooth & Simple!

On-The-Job Training Is made Intuitive & Easy With WalkMe's On-Screen Guidance Tool.  Claim Your Free WalkMe Account Now

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Entity Framework is a powerful tool to help you interact with the DataBase but still doesn't help much when we have a Stored Procedure that returns more than one resultset. The solution takes some of out-of-the-box thinking; read on!
This post looks at MongoDB and MySQL, and covers high-level MongoDB strengths, weaknesses, features, and uses from the perspective of an SQL user.
This is a high-level webinar that covers the history of enterprise open source database use. It addresses both the advantages companies see in using open source database technologies, as well as the fears and reservations they might have. In this…
Monitoring a network: how to monitor network services and why? Michael Kulchisky, MCSE, MCSA, MCP, VTSP, VSP, CCSP outlines the philosophy behind service monitoring and why a handshake validation is critical in network monitoring. Software utilized …

688 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question