docs: public Timestamp getTimestamp(int columnIndex,
                                    Calendar cal) throws SQLException {
  
          TimestampData t = (TimestampData) getColumnInType(columnIndex,
              Type.SQL_TIMESTAMP);
  
          if (t == null) {
              return null;
          }
  
          long millis = t.getSeconds() * 1000;
  
          if (resultMetaData.columnTypes[--columnIndex]
                  .isDateTimeTypeWithZone()) {}
          else {
  
              // UTC - calZO == (UTC - sessZO) + (sessionZO - calZO)
              if (cal != null) {
                  int zoneOffset = HsqlDateTime.getZoneMillis(cal, millis);
  
                  millis += session.getZoneSeconds() * 1000 - zoneOffset;
              }
          }
  
          Timestamp ts = new Timestamp(millis);
  
          ts.setNanos(t.getNanos());
  
          return ts;
      }