exec sys.sp_who2
--or
select
    er.session_id
  , ses.STATUS
  , ses.login_name
  , ses.host_name
  , er.blocking_session_id
  , db_name(er.database_id) as [db_name]
  , er.command
  , object_name(st.objectid) as object_name
  , er.cpu_time
  , er.start_time
  , cast(getdate() - er.start_time as time) as elapsed_time
  , st.text as query
from sys.dm_exec_requests er
    outer apply sys.dm_exec_sql_text(er.sql_handle) st
    left join sys.dm_exec_sessions ses on ses.session_id = er.session_id
    left join sys.dm_exec_connections con on con.session_id = ses.session_id
where er.session_id > 50

public static T ExecuteCommand(Func<SqlCommand,  T> action)
{
	using (var cnn = _cnnfactory.GetSqlClientConnection())
	using (var cmd = cnn.CreateCommand())
	{
		cnn.Open();
		
		return action(cmd);
		
		//cnn.Close(); вообще не обязательно явно закрывать соединение, будет вызван Dispose()
	}
}

public static List<T> ReadList<T>(this SqlCommand cmd, Func<DataReader, T> func)
{
	using (var reader = cmd.ExecuteReader())
	{
		var result = new List<T>();
		while (reader.Read())
		{
			result.Add(func(reader));
		}
		
		//reader.Close(); вообще не обязательно явно закрывать ридер, будет вызван Dispose()
		
		return result;
	}
}

// использование:
public List<Dto> GetSomeData()
{
	return ExecuteCommand(cmd => {
		cmd.CommandText = "select Id, Name from dbo.MyFavoriteTable";
		
		return cmd.ReadList(reader => new Dto {
			Id = reader.GetInt32("Id"),
			Name = reader.GetString("Name")
		});
	});
}

public string fromOffice =>  this.fromOfficeId != null ? Office.GetById(this.fromOfficeId ?? 0)?.nameOffice : "";

using (var connection = DBModule.NewSqlConnection())
{
     var sql = @"
select rt.*, o.nameOffice as fromOffice 
from requestTransactions rt
    left join dic_company_offices o on o.Id = rt.office_id
where rt.isDeleted = 0
";
     return connection.Query<RequestTransaction>(sql).ToList();
}

//и

public class RequestTransaction
{
           [Key]
           public int id { get; set; }

          [Write(false)]
          public string fromOffice { get; set; }
}