Passing an object collection as a parameter into SQL Server stored procedure - asp.net

Question

I have a general question on whether something can be done - and whether it will be the most efficient way of doing it !
To summarise: can I pass an object collection as a parameter to a stored procedure?
Let's say that I have a SQL Server table called Users [UserID, Forename, Surname]
and another table called Hobbies [HobbyID, UserID, HobbyName, HobbyTypeID]
This set up is to record multiple hobbies against a user.
In my application, I want to update the user record.
Normally - I would update the user table and then in code, loop through each hobby and update the hobbies table record by record.
If I'm updating the user forename and 2 of their hobbies, this would require 3 calls to the database.
(1 call to a stored procedure to update the forename/surname, and 2 calls to a stored procedure to update the 2 hobby records)
My question is:
Can I make just 1 call to the database by passing all the parameters to just 1 stored procedure.
eg.
intUserID = 1
strForename = "Edward"
strSurname = "ScissorHands"
dim objHobbyCollection as New List(Of Hobby)
'Assume that I have 2 hobby objects, each with their hobbyID, UserID, HobbyName & HobbyTypeID
Dim params As SqlParameter()
params = New SqlParameter() {
New SqlParameter("#UserID", intUserID),
New SqlParameter("#Forename", strForename),
New SqlParameter("#Surname", strSurname),
New SqlParameter("#Hobbies", objHobbyCollection)
}
Can I do this ? (and which way would be more efficient?)
What would the Stored Procedure look like ?
ALTER PROCEDURE [dbo].[User_Update]
#UserID INT
,#Forename NVARCHAR(50) = NULL
,#Surname NVARCHAR(50) = NULL
,#Hobbies ??????????????

Answer 1

Assuming SQL Server 2008+, you can do this using a table-valued parameter. First in SQL Server create a table type:
CREATE TYPE dbo.HobbiesTVP AS TABLE
(
HobbyID INT PRIMARY KEY,
HobbyName NVARCHAR(50),
HobbyTypeID INT
);
Then your stored procedure would say:
#Hobbies dbo.HobbiesTVP READONLY
In C# (sorry I don't know vb.net equivalent) it would be as follows (but if you just have one UserID, this doesn't need to be part of the collection, does it?):
// as Steve pointed out, you may need to have your hobbies in a DataTable.
DataTable HobbyDataTable = new DataTable();
HobbyDataTable.Columns.Add(new DataColumn("HobbyID"));
HobbyDataTable.Columns.Add(new DataColumn("HobbyName"));
HobbyDataTable.Columns.Add(new DataColumn("HobbyTypeID"));
// loop through objHobbyCollection and add the values to the DataTable,
// or just populate this DataTable in the first place
using (connObject)
{
SqlCommand cmd = new SqlCommand("dbo.User_Update", connObject);
cmd.CommandType = CommandType.StoredProcedure;
// other params, e.g. #UserID
SqlParameter tvparam = cmd.Parameters.AddWithValue("#Hobbies", HobbyDataTable);
tvparam.SqlDbType = SqlDbType.Structured;
// ...presumably ExecuteNonQuery()
}