code: public function fieldExists($strField, $strTable, $blnNoCache=false)
  	{
  		if ($strField == '' || $strTable == '')
  		{
  			return false;
  		}
  
  		foreach ($this->listFields($strTable, $blnNoCache) as $arrField)
  		{
  			if ($arrField['name'] == $strField && $arrField['type'] != 'index')
  			{
  				return true;
  			}
  		}
  
  		return false;
  	}
docs: Determine if a particular column exists
  
  @param string  $strField   The field name
  @param string  $strTable   The table name
  @param boolean $blnNoCache If true, the cache will be bypassed
  
  @return boolean True if the field exists