private UpdateSql buildUpdateSqlPrefix(JobQueueReq request) {
        return new UpdateSql(getSqlTemplate())
                .update()
                .table(getTableName(request))
                .setOnNotNull("cron_expression", request.getCronExpression())
                .setOnNotNull("need_feedback", request.getNeedFeedback())
                .setOnNotNull("ext_params", JSON.toJSONString(request.getExtParams()))
                .setOnNotNull("trigger_time", JdbcTypeUtils.toTimestamp(request.getTriggerTime()))
                .setOnNotNull("priority", request.getPriority())
                .setOnNotNull("max_retry_times", request.getMaxRetryTimes())
                .setOnNotNull("rely_on_prev_cycle", request.getRelyOnPrevCycle() == null ? true : request.getRelyOnPrevCycle())
                .setOnNotNull("submit_node_group", request.getSubmitNodeGroup())
                .setOnNotNull("task_tracker_node_group", request.getTaskTrackerNodeGroup())
                .setOnNotNull("repeat_count", request.getRepeatCount())
                .setOnNotNull("repeat_interval", request.getRepeatInterval())
                .setOnNotNull("gmt_modified", SystemClock.now());
    }
@author Robert HG (254963746@qq.com) on 5/31/15.
lts-core/src/main/java/com/github/ltsopensource/queue/mysql/AbstractMysqlJobQueue.java