function begin_updates()
{
  var submitted = document.getElementById('submitted');

  // Block dbmake from starting up again if bo_error_message()
  // occurs and user clicks Back in the browser.
  if (Number(submitted.value) == 0)
  {
    submitted.value = '1'; /* submit only once */
    document.forms['jynx'].submit();
    window.setInterval(get_pbar_percent, 1000); /* pbar.js */
  }
}

function no_unmatched_fields()
{
  if (unmatched_fields > 0)
  {
    alert(unmatched_fields_msg);
    return false;
  }

  return true;
}

function show_field_mappings()
{
  var jynx  = document.getElementById('jynx');
  var match = document.getElementById('match');

  match.value = 1;
  jynx.action = pier_imports + '/dbupload.cgi';
  jynx.submit();
}

function load_worksheet()
{
  var jynx = document.getElementById('jynx');
  var loading = document.getElementById('loading');
  var upload_columns = document.getElementById('upload_columns');

  upload_columns.value = '';
  loading.style.display = '';
  jynx.action = pier_imports + '/dbupload.cgi';
  jynx.submit();
}

function emit_fields(selectList)
{
  var fieldname, fieldnum, optgroup;
  var j = selectList.options.length;
  var i, fd;

  if (j <= 2)
  {
    for (i = 0; i < fields.length; i++, j++)
    {
      fd = fields[i].split('|');

      fieldname = fd[0];
      fieldnum  = fd[1];
      optgroup  = fd[2]; 
    
      selectList.options[j] = new Option(fieldname, fieldnum, false, false);

      if (optgroup != '~')
        add_optgroup(selectList, optgroup, j);
    }
  }
}

function add_optgroup(db_fields, section_name, index)
{
  var options = db_fields.options;
  var optgroup = document.createElement("optgroup");

  optgroup.setAttribute("label", section_name);
  optgroup.appendChild(options[index]);
  db_fields.insertBefore(optgroup, options[index]);
}