DataSet ds = Api.Zselect(MercatorUi.Globals.RepData, "select * from cli");
if (ds == null)
     return ;
string fileName = @"c:\test\testcli.xlsx";
if (MercatorExporter.Exporter Export(ds.Tables[0], MercatorExporter.ExporterFormats.Excel, fileName))
    System.Diagnostics.Process.Start(fileName);