(window.webpackJsonp=window.webpackJsonp||[]).push([[398],{965:function(t,e,v){"use strict";v.r(e);var _=v(70),a=Object(_.a)({},(function(){var t=this,e=t.$createElement,v=t._self._c||e;return v("ContentSlotsDistributor",{attrs:{"slot-key":t.$parent.slotKey}},[v("h1",{attrs:{id:"数据模式"}},[v("a",{staticClass:"header-anchor",attrs:{href:"#数据模式"}},[t._v("#")]),t._v(" 数据模式")]),t._v(" "),v("h2",{attrs:{id:"数据模型"}},[v("a",{staticClass:"header-anchor",attrs:{href:"#数据模型"}},[t._v("#")]),t._v(" 数据模型")]),t._v(" "),v("p",[t._v("我们以风电场物联网场景为例，说明如何在 IoTDB 中创建一个正确的数据模型。")]),t._v(" "),v("p",[t._v("根据企业组织结构和设备实体层次结构，我们将其物联网数据模型表示为如下图所示的属性层级组织结构，即电力集团层-风电场层-实体层-物理量层。其中 ROOT 为根节点，物理量层的每一个节点为叶子节点。IoTDB 采用树形结构定义数据模式，以从ROOT 节点到叶子节点的路径来命名一个时间序列，层次间以“.”连接。例如，下图最左侧路径对应的时间序列名称为"),v("code",[t._v("ROOT.ln.wf01.wt01.status")]),t._v("。")]),t._v(" "),v("img",{staticStyle:{width:"100%","max-width":"800px","max-height":"600px","margin-left":"auto","margin-right":"auto",display:"block"},attrs:{src:"https://user-images.githubusercontent.com/19167280/123542457-5f511d00-d77c-11eb-8006-562d83069baa.png"}}),t._v(" "),v("p",[t._v("IoTDB模型结构涉及如下基本概念：")]),t._v(" "),v("ul",[v("li",[t._v("物理量（Measurement，也称工况、字段 field）")])]),t._v(" "),v("p",[v("strong",[t._v("一元或多元物理量")]),t._v("，是在实际场景中检测装置所记录的测量信息，且可以按一定规律变换成为电信号或其他所需形式的信息输出并发送给 IoTDB。在 IoTDB 当中，存储的所有数据及路径，都是以物理量为单位进行组织。")]),t._v(" "),v("ul",[v("li",[t._v("物理分量（SubMeasurement、分量）")])]),t._v(" "),v("p",[t._v("在多元物理量中，包括多个分量。如 GPS 是一个多元物理量，包含3个分量：经度、维度、海拔。多元物理量通常被同时采集，共享时间列。")]),t._v(" "),v("p",[t._v("一元物理量则将分量名和物理量名字重合。如温度是一个一元物理量。")]),t._v(" "),v("ul",[v("li",[t._v("实体（Entity，也称设备，device）")])]),t._v(" "),v("p",[v("strong",[t._v("一个物理实体")]),t._v("，是在实际场景中拥有物理量的设备或装置。在IoTDB当中，所有的物理量都有其对应的归属实体。")]),t._v(" "),v("ul",[v("li",[t._v("存储组（Storage group）")])]),t._v(" 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