Есть такой код.

OleDbConnection oConnection = new OleDbConnection("Provider=SQLOLEDB;data source=.;initial catalog=Northwind;trusted_connection=yes;");
using (DbManager db = new DbManager(oConnection))
{
    try
    {
        DataTable dataTable = null;
        dataTable = db.SetCommand("select * from Employees where EmployeesID = @EmployeesID",
            db.InputParameter("@EmployeesID", 1))
            .ExecuteDataTable();
        Console.Out.WriteLine("dataTable.Rows.Count = {0}", dataTable.Rows.Count);
    }
    catch(OleDbException ex)
    {
        Console.Out.WriteLine(ex.ToString());
    }
}
Console.In.ReadLine();

Вроде всё написал правильно, а не работает Пишет ошибку

System.Data.OleDb.OleDbException: Must declare the variable '@EmployeesID'.
   at System.Data.OleDb.OleDbCommand.ExecuteCommandTextErrorHandling(Int32 hr)
   at System.Data.OleDb.OleDbCommand.ExecuteCommandTextForSingleResult(tagDBPARAMS dbParams, Object& executeResult)
   at System.Data.OleDb.OleDbCommand.ExecuteCommandText(Object& executeResult)
   at System.Data.OleDb.OleDbCommand.ExecuteCommand(CommandBehavior behavior, Object& executeResult)
   at System.Data.OleDb.OleDbCommand.ExecuteReaderInternal(CommandBehavior behavior, String method)
   at System.Data.OleDb.OleDbCommand.ExecuteReader(CommandBehavior behavior)
   at System.Data.OleDb.OleDbCommand.System.Data.IDbCommand.ExecuteReader(CommandBehavior behavior)
   at System.Data.Common.DbDataAdapter.FillFromCommand(Object data, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior)
   at System.Data.Common.DbDataAdapter.Fill(DataTable dataTable, IDbCommand command, CommandBehavior behavior)
   at System.Data.Common.DbDataAdapter.Fill(DataTable dataTable)
   at Rsdn.Framework.Data.DbManager.ExecuteDataTable(DataTable dataTable) in D:\PROJECTS\SalesChampionImport\RFD\DbManager.cs:line 2738
   at Rsdn.Framework.Data.DbManager.ExecuteDataTable() in D:\PROJECTS\SalesChampionImport\RFD\DbManager.cs:line 2714
   at TestRFD.Class1.Main(String[] args) in d:\projects\testrfd\testrfd\class1.cs:line 26

Помогите разобратся в чём проблема...