I have a many to many table relation ship:
CUS_Phone: holds its own unique id, the cus id from its parent table as well as name title dates, etc…
CUS_Phone_JCT: Holds its own unique id, the id from the CUS_Phone and the id from CUS_Phone
CUS_Phone: Holds its own unique id, and the phone number
Here I have a join query to retrieve all the customer names and phone numbers:
var q = from c in CUS_Contact
join cp in CUS_Phone_JCT on c.Id equals cp.Contact_Id into cp2
from cp3 in cp2.DefaultIfEmpty()
join p in CUS_Phone on cp3.Phone_Id equals p.Id into p2
from p3 in p2.DefaultIfEmpty()
where c.Cus_Id == 9120
select new
{
c.Id,
c.Cus_Id,
c.Namefirst,
c.Namemiddle,
c.Namelast,
cp3.Phone.Phone,
c.Title,
c.Dept,
c.Des, c.Datecreate,
c.Dateupdate,
c.Usr_idcreate,
c.Usr_idupdate
};
foreach(var v in q){
Console.WriteLine(v.Id + "-" + v.Namefirst + "-" + v.Phone);
}
How can I go about formulating the query to group the numbers per customer? I want to see distinct customers with a list of numbers per customer(IEnumerable List). Theres a similar example in the LINQPad spanishOrders query, but they group the order details per order. Im not sure how to do this with my schema. Thanks!
EDIT: Here’s the sql outputted from the first answer…
-- Region Parameters
DECLARE @p0 Int SET @p0 = 4
-- EndRegion
SELECT (
SELECT [t8].[id]
FROM (
SELECT TOP (1) [t6].[id]
FROM [CUS_Contact] AS [t6]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t7] ON [t6].[id] = [t7].[Contact_Id]
WHERE [t2].[id] = [t6].[id]
) AS [t8]
) AS [Id], (
SELECT [t11].[Cus_Id]
FROM (
SELECT TOP (1) [t9].[Cus_Id]
FROM [CUS_Contact] AS [t9]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t10] ON [t9].[id] = [t10].[Contact_Id]
WHERE [t2].[id] = [t9].[id]
) AS [t11]
) AS [Cus_Id], (
SELECT [t14].[namefirst]
FROM (
SELECT TOP (1) [t12].[namefirst]
FROM [CUS_Contact] AS [t12]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t13] ON [t12].[id] = [t13].[Contact_Id]
WHERE [t2].[id] = [t12].[id]
) AS [t14]
) AS [Namefirst], (
SELECT [t17].[namemiddle]
FROM (
SELECT TOP (1) [t15].[namemiddle]
FROM [CUS_Contact] AS [t15]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t16] ON [t15].[id] = [t16].[Contact_Id]
WHERE [t2].[id] = [t15].[id]
) AS [t17]
) AS [Namemiddle], (
SELECT [t20].[namelast]
FROM (
SELECT TOP (1) [t18].[namelast]
FROM [CUS_Contact] AS [t18]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t19] ON [t18].[id] = [t19].[Contact_Id]
WHERE [t2].[id] = [t18].[id]
) AS [t20]
) AS [Namelast], (
SELECT [t23].[title]
FROM (
SELECT TOP (1) [t21].[title]
FROM [CUS_Contact] AS [t21]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t22] ON [t21].[id] = [t22].[Contact_Id]
WHERE [t2].[id] = [t21].[id]
) AS [t23]
) AS [Title], (
SELECT [t26].[dept]
FROM (
SELECT TOP (1) [t24].[dept]
FROM [CUS_Contact] AS [t24]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t25] ON [t24].[id] = [t25].[Contact_Id]
WHERE [t2].[id] = [t24].[id]
) AS [t26]
) AS [Dept], (
SELECT [t29].[des]
FROM (
SELECT TOP (1) [t27].[des]
FROM [CUS_Contact] AS [t27]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t28] ON [t27].[id] = [t28].[Contact_Id]
WHERE [t2].[id] = [t27].[id]
) AS [t29]
) AS [Des], (
SELECT [t32].[datecreate]
FROM (
SELECT TOP (1) [t30].[datecreate]
FROM [CUS_Contact] AS [t30]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t31] ON [t30].[id] = [t31].[Contact_Id]
WHERE [t2].[id] = [t30].[id]
) AS [t32]
) AS [Datecreate], (
SELECT [t35].[dateupdate]
FROM (
SELECT TOP (1) [t33].[dateupdate]
FROM [CUS_Contact] AS [t33]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t34] ON [t33].[id] = [t34].[Contact_Id]
WHERE [t2].[id] = [t33].[id]
) AS [t35]
) AS [Dateupdate], (
SELECT [t38].[usr_idcreate]
FROM (
SELECT TOP (1) [t36].[usr_idcreate]
FROM [CUS_Contact] AS [t36]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t37] ON [t36].[id] = [t37].[Contact_Id]
WHERE [t2].[id] = [t36].[id]
) AS [t38]
) AS [Usr_idcreate], (
SELECT [t41].[usr_idupdate]
FROM (
SELECT TOP (1) [t39].[usr_idupdate]
FROM [CUS_Contact] AS [t39]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t40] ON [t39].[id] = [t40].[Contact_Id]
WHERE [t2].[id] = [t39].[id]
) AS [t41]
) AS [Usr_idupdate], [t2].[id] AS [id2]
FROM (
SELECT [t0].[id]
FROM [CUS_Contact] AS [t0]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t1] ON [t0].[id] = [t1].[Contact_Id]
GROUP BY [t0].[id]
) AS [t2]
WHERE ((
SELECT [t5].[Cus_Id]
FROM (
SELECT TOP (1) [t3].[Cus_Id]
FROM [CUS_Contact] AS [t3]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t4] ON [t3].[id] = [t4].[Contact_Id]
WHERE [t2].[id] = [t3].[id]
) AS [t5]
)) = @p0
GO
-- Region Parameters
DECLARE @x1 Int SET @x1 = 9327
-- EndRegion
SELECT [t2].[phone] AS [value]
FROM [CUS_Contact] AS [t0]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t1] ON [t0].[id] = [t1].[Contact_Id]
LEFT OUTER JOIN [CUS_Phone] AS [t2] ON [t2].[id] = [t1].[Phone_Id]
WHERE @x1 = [t0].[id]
GO
-- Region Parameters
DECLARE @x1 Int SET @x1 = 9328
-- EndRegion
SELECT [t2].[phone] AS [value]
FROM [CUS_Contact] AS [t0]
LEFT OUTER JOIN [CUS_Phone_JCT] AS [t1] ON [t0].[id] = [t1].[Contact_Id]
LEFT OUTER JOIN [CUS_Phone] AS [t2] ON [t2].[id] = [t1].[Phone_Id]
WHERE @x1 = [t0].[id]
I’m a bit confused by your use of
cp3.Phone.Phonein addition to yourjoinagainstCUS_Phone, so I’m going to assume the former means you don’t need the latter. Otherwise, just switch inp3forcp3in thejoinand adjust theg.Select()accordingly.That said, you should be able to simply group on the contact ID:
A few shots in the dark to improve performance:
You might also try grouping by a composite key (with all your
cfields) instead of c.Id:Update: Tweaked the composite key example to only group the Phone value, since everything else you need should be in the key.
Update 2: You might be able to simplify things quite a bit by embedding a subquery: