How to tell if SQL Server is local or remote? - sql-server

Question

In my app the users gets to pick from a list of SQL Server in the network. The thing is I need to know if the chosen instance is a local or remote computer.
Is there a way I can ask that SQL instance what computer is she on? Is there a way a can figure that out?
Edit1: I want to know the host name where the SQL Server is hosted so I can then compare that to System.Environment.MachineName and know for sure is that Sql Server is running on the same machine where my app is running
Edit2: ##servername returned my computername\sqlinstance while SELECT SERVERPROPERTY('MachineName') returns just the computername, which is exactly what I want

Answer 1

Use ##Servername, for example:
SELECT ##servername
Alternately you could do this
SELECT SERVERPROPERTY('MachineName')
From MSDN on the differences between these approaches:
The ServerName property of the
SERVERPROPERTY function and
##SERVERNAME return similar
information. The ServerName property
provides the Windows server and
instance name that together make up
the unique server instance.
##SERVERNAME provides the currently
configured local server name.
The ServerName property and
##SERVERNAME return the same
information if the default server name
at the time of installation has not
been changed.
If the local server name has been
changed from the default server name
at installation time, ##SERVERNAME
returns the new name.

Answer 2

Do you actually have login permissions on all the instance(s) of SQL Server? If so you could execute sp_helpserver or ##servername and compare the name returned with Environment.MachineName.
If you don't have login access, you can write a small C# console program to return the server name of every SQL Server instance on the local network:
using System;
using System.Data.Sql;
class Program
{
static void Main()
{
// Retrieve the enumerator instance and then the data.
SqlDataSourceEnumerator instance =
SqlDataSourceEnumerator.Instance;
System.Data.DataTable table = instance.GetDataSources();
// Display the contents of the table.
// The first column is the server name.
DisplayData(table);
Console.WriteLine("Press any key to continue.");
Console.ReadKey();
}
private static void DisplayData(System.Data.DataTable table)
{
foreach ( System.Data.DataRow row in table.Rows )
{
foreach ( System.Data.DataColumn col in table.Columns )
{
Console.WriteLine("{0} = {1}", col.ColumnName, row[col]);
}
Console.WriteLine("============================");
}
}
}

Answer 3

sp_who2 returns the hostname