code: public UniqueKeyInformation getUKInfoByColNames(final String _ukColName)
      {
          return (_ukColName != null)
                 ? this.ukColMap.get(_ukColName.toUpperCase())
                 : null;
      }
docs: <p>Returns for given name of unique key <code>_ukColName</code> (of the
  SQL table) the information about the unique key, or if the given name of
  unique key is not defined, a <code>null</code> is returned.</p>
  <p>The name of the given unique key is searched independently of upper
  and / or lower case.</p>
  
  @param _ukColName  name of column names for which the unique key is
  searched
  @return unique key information
  @see #ukColMap