code: public UniqueKeyInformation getUKInfo(final String _ukName)
      {
          return (_ukName != null)
                 ? this.ukMap.get(_ukName.toUpperCase())
                 : null;
      }
docs: <p>Returns for given name of unique key (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 _ukName   name of unique key which is searched
  @return unique key information
  @see #ukMap