Question

I have two tables: baswareCatalog.FlowCurrent and baswareCatalog.Doc.
They both contain the attribute DocId.
The Doc-table also has the attributes LastExpireDate and Status.
FlowCurrent-table also has the attribute RecipientName.
I want to retrieve a collection of Doc, where the DocId of the item is the same in both tables.

Furthermore, this condition must be true: flowCurrent.RecipientName.Contains(userFullName)

I tried the following, but I don’t know if it is correct.

var docitemIQueryable = from flowCurrent in baswareCatalog.FlowCurrent join 
                        document in baswareCatalog.Docs on 
                        flowCurrent.DocId equals document.DocId 
                        where flowCurrent.RecipientName.Contains(userFullName) 
                        select new
                        {
                          Items = baswareCatalog
                                  .Docs
                                  .Where(b => b.DocId == flowCurrent.DocId)
                        };

The return-value is

'interface System.Linq.IQueryable<out T>'.
T is 'a' 
Anonymous Types: 'a is new {IQueryable<Doc> Items }'

How do I retrieve a collection of Doc that I can iterate over?

Answer 1

Two things:

1. System.Linq.IQueryable is a collection that you can iterate over. You can put it in a foreach loop or do whatever you want with it. Or you can use .ToList() if you want to immediately materialize it.
2. You’re doing extra work that you don’t need to do in your query. You’re doing a join between FlowCurrent and Docs, but then you’re taking the results and going right back to Docs again. You don’t need to do that.

Assuming what you care about is just the stuff in Docs, try this:

var docitemIQueryable = from flowCurrent in baswareCatalog.FlowCurrent 
                        join document in baswareCatalog.Docs on 
                            flowCurrent.DocId equals document.DocId 
                        where flowCurrent.RecipientName.Contains(userFullName) 
                        select document;

That will give you a collection of rows with all the fields in Docs. If you need some of the stuff in FlowCurrent as well then you’ll need to do something more like this:

var docitemIQueryable = from flowCurrent in baswareCatalog.FlowCurrent 
                        join document in baswareCatalog.Docs on 
                            flowCurrent.DocId equals document.DocId 
                        where flowCurrent.RecipientName.Contains(userFullName) 
                        select new {
                            document.DocId, flowCurrent.blahblah, ...
                        };