| (window.webpackJsonp=window.webpackJsonp||[]).push([[476],{873:function(s,a,t){"use strict";t.r(a);var n=t(29),e=Object(n.a)({},(function(){var s=this,a=s._self._c;return a("ContentSlotsDistributor",{attrs:{"slot-key":s.$parent.slotKey}},[a("h1",{attrs:{id:"元数据模板"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#元数据模板"}},[s._v("#")]),s._v(" 元数据模板")]),s._v(" "),a("h2",{attrs:{id:"问题背景"}},[a("a",{staticClass:"header-anchor",attrs:{href:"#问题背景"}},[s._v("#")]),s._v(" 问题背景")]),s._v(" "),a("p",[s._v("对于大量的同类型的实体，每一个实体下的物理量都相同，为每个序列注册时间序列一方面时间序列的元数据将占用较多的内存资源，另一方面，大量序列的维护工作也会十分复杂。")]),s._v(" "),a("p",[s._v("为了实现同类型不同实体的物理量元数据共享，减少元数据内存占用，同时简化同类型实体的管理，IoTDB引入元数据模板功能。")]),s._v(" "),a("p",[s._v("下图展示了一个燃油车场景的数据模型，各地区的多台燃油车的速度、油量、加速度、角速度四个物理量将会被采集，显然这些燃油车实体具备相同的物理量。")]),s._v(" 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