taos-query_物联网平台_边缘计算网关

概述

【taos-query】 节点是用来与 TDengine（TaosDB）进行交互的节点，特别是用于执行 SQL 查询 操作，来获取存储在 TDengine 数据库中的时序数据。Node-RED 是一个基于流的开发工具，广泛用于 IoT（物联网）设备、传感器数据的处理和可视化。而 taos-query 节点则作为 TDengine 数据库的接口，允许用户在 Node-RED 流程中查询时序数据。

输入

#一般是要写入sql语句
msg.payload

输出

#一般是命令执行得到的回执信息
msg.payload

示例及其代码

准备工作：下载创建链接所需的数据库及其可视化工具

本次示例用到的软件为：TDengine (taos) + DBeaver

开启数据库远程访问并通过可视化工具连接数据库实例：

节点连接图示：

function 节点配置：

taos query节点：

完整演示：

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