private static int setTimeZone(
      CliContext ctx, String specialCmd, String cmd, IoTDBConnection connection) {
    String[] values = specialCmd.split("=");
    if (values.length != 2) {
      ctx.getPrinter()
          .println(
              String.format("Time zone format error, please input like %s=+08:00", SET_TIME_ZONE));
      return CODE_ERROR;
    }
    try {
      connection.setTimeZone(cmd.split("=")[1].trim());
    } catch (Exception e) {
      ctx.getPrinter().println(String.format("Time zone format error: %s", e.getMessage()));
      return CODE_ERROR;
    }
    ctx.getPrinter().println("Time zone has set to " + values[1].trim());
    return CODE_OK;
  }
If cli has not specified a zoneId, it will be set to cli's system timezone by default otherwise
for insert and query accuracy cli should set timezone the same for all sessions.

@param specialCmd
@param cmd
@param connection
@return execute result code
iotdb-client/cli/src/main/java/org/apache/iotdb/cli/AbstractCli.java