code: @Override
      protected void initTableInfoUniqueKeys(final Connection _con,
                                             final String _sql,
                                             final Map<String, TableInformation> _cache4Name)
          throws SQLException
      {
          super.initTableInfoUniqueKeys(_con, PostgreSQLDatabase.SQL_UNIQUE_KEYS, _cache4Name);
      }
docs: Overwrites the original method to specify SQL statement
  {@link #SQL_UNIQUE_KEYS} as replacement because the JDBC driver for
  PostgreSQL does not handle matching table names.
  
  @param _con          SQL connection
  @param _sql          SQL statement (not used)
  @param _cache4Name   map used to fetch depending on the table name the
  related table information
  @throws SQLException if unique keys could not be fetched
  @see #SQL_UNIQUE_KEYS