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Collection inside collection in sql server view

Hi.
I have two tables. relation 1:N. when I create a view, I got one record for each item in the N table. How could I get a single record with a collection of the N table inside the first record? Is it possible?
From this view, we will create a stored procedure and mapped it with EF 6 to use into a c# web app.

thx in advance
example.png

Vitor Montalvão

A GROUP BY clause will do the trick. You just need to decide if you want the MIN or MAX account:

SELECT users.Name, MAX(accounts.Account)
FROM accounts
	INNER JOIN users ON (accounts.userid = users.userid)
GROUP BY users.Name

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Deraldo Silva

ASKER

Hi Vitor, thx for your attention.
with this query I got the number of accounts that a user owns. I need this (in c# terms)

public class User
{
public string Name { get; set; }
public ICollection<string> accounts { get; set; }
}
or,
[ {"nome1", [{"1"}, {"2"},{"3"},{"4"}]}, {... }]

regards

Vitor Montalvão

Deraldo, I'm afraid I can't help you with C#. I work only with SQL Server. Sorry.

Deraldo Silva

ASKER

Vitor, I do not have any question about c#, it's an example. because of this, I put two different examples, in c# and in json.
ok. let me explain better.
My question is about sql server.
as I show in the picture, when i did my view, the sql is

SELECT dbo.USERS.Name, dbo.ACCOUNTS.Account
FROM dbo.ACCOUNTS INNER JOIN
dbo.USERS ON dbo.ACCOUNTS.UserID = dbo.USERS.UserID

but, with this query I got this result
Nome1 1
Nome1 2
Nome1 3
Nome1 4

If I have several fields in the Users table, these fields will be repeated, for all accounts, right? like this
Nome1 f1 f2 f3 f4 f5 f6 1
Nome1 f1 f2 f3 f4 f5 f6 2 and so on.

what I want: a single record where the accounts is another record set, inside the first one.

I don't know if it is possible.
maybe a select inside a select.

Vitor Montalvão

Deraldo, can you post an example of the output you want?
Maybe it's better for me to understand with an example.
Thanks.

Deraldo Silva

ASKER

thats the problem. I don't know how to show you the example as a sql result. I think that there is no such thing in sql. a recordset inside an record. a list as field element. wow! maybe converting one recordset into a xml value before output. So the user record, with all its fields and one field will be an xml with several accounts inside it.
is it possible with one view? or one stored procedure?

sorry for the inconvenience, this is like an handshake between two different expertises.

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Vitor Montalvão

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Deraldo Silva

ASKER

yeah. that's what I realize.

anyway, thx for your attention.

Olaf Doschke

Linq can do what you need, more precise the linq extension methods, not a linq query.

            using (var entities = new YourDatabaseEntities())
            {
                Users = new Collection<User>(
                    entities.users.Select(usr => new User
                    {
                        Name =  usr.UserName,
                        Accounts = usr.accounts.Select(acc => new Account
                        {
                            AccountNo = acc.AccountNumber
                        })
                    }));
            }

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The User class then will need to have a string Name property and a IEnumerable<Account> Accounts property.

Bye, Olaf.