Match given field name in Config table and return corresponding value.

    Parameters
    ----------
      fieldName : string
        String matching Name column in Config table.

    Returns
    ----------
      string or None
        If a match is found the corresponding entry in the Value column of the
        database table is returned, otherwise None is returned (or if multiple
        matches are found a fatal error is raised).

def GetConfigValue(self, fieldName):
    """
    Match given field name in Config table and return corresponding value.

    Parameters
    ----------
      fieldName : string
        String matching Name column in Config table.

    Returns
    ----------
      string or None
        If a match is found the corresponding entry in the Value column of the
        database table is returned, otherwise None is returned (or if multiple
        matches are found a fatal error is raised).
    """
    result = self._ActionDatabase("SELECT Value FROM Config WHERE Name=?", (fieldName, ))

    if result is None:
      return None
    elif len(result) == 0:
      return None
    elif len(result) == 1:
      goodlogging.Log.Info("DB", "Found database match in config table {0}={1}".format(fieldName, result[0][0]), verbosity=self.logVerbosity)
      return result[0][0]
    elif len(result) > 1:
      goodlogging.Log.Fatal("DB", "Database corrupted - multiple matches found in config table {0}={1}".format(fieldName, result))