"use strict";(self.webpackChunk=self.webpackChunk||[]).push([[1453],{3905:(e,t,n)=>{n.d(t,{Zo:()=>s,kt:()=>d});var r=n(7294);function a(e,t,n){return t in e?Object.defineProperty(e,t,{value:n,enumerable:!0,configurable:!0,writable:!0}):e[t]=n,e}function o(e,t){var n=Object.keys(e);if(Object.getOwnPropertySymbols){var r=Object.getOwnPropertySymbols(e);t&&(r=r.filter((function(t){return Object.getOwnPropertyDescriptor(e,t).enumerable}))),n.push.apply(n,r)}return n}function i(e){for(var t=1;t<arguments.length;t++){var n=null!=arguments[t]?arguments[t]:{};t%2?o(Object(n),!0).forEach((function(t){a(e,t,n[t])})):Object.getOwnPropertyDescriptors?Object.defineProperties(e,Object.getOwnPropertyDescriptors(n)):o(Object(n)).forEach((function(t){Object.defineProperty(e,t,Object.getOwnPropertyDescriptor(n,t))}))}return e}function c(e,t){if(null==e)return{};var n,r,a=function(e,t){if(null==e)return{};var n,r,a={},o=Object.keys(e);for(r=0;r<o.length;r++)n=o[r],t.indexOf(n)>=0||(a[n]=e[n]);return a}(e,t);if(Object.getOwnPropertySymbols){var o=Object.getOwnPropertySymbols(e);for(r=0;r<o.length;r++)n=o[r],t.indexOf(n)>=0||Object.prototype.propertyIsEnumerable.call(e,n)&&(a[n]=e[n])}return a}var l=r.createContext({}),u=function(e){var t=r.useContext(l),n=t;return e&&(n="function"==typeof e?e(t):i(i({},t),e)),n},s=function(e){var t=u(e.components);return r.createElement(l.Provider,{value:t},e.children)},p="mdxType",h={inlineCode:"code",wrapper:function(e){var t=e.children;return r.createElement(r.Fragment,{},t)}},g=r.forwardRef((function(e,t){var n=e.components,a=e.mdxType,o=e.originalType,l=e.parentName,s=c(e,["components","mdxType","originalType","parentName"]),p=u(n),g=a,d=p["".concat(l,".").concat(g)]||p[g]||h[g]||o;return n?r.createElement(d,i(i({ref:t},s),{},{components:n})):r.createElement(d,i({ref:t},s))}));function d(e,t){var n=arguments,a=t&&t.mdxType;if("string"==typeof e||a){var o=n.length,i=new Array(o);i[0]=g;var c={};for(var l in t)hasOwnProperty.call(t,l)&&(c[l]=t[l]);c.originalType=e,c[p]="string"==typeof e?e:a,i[1]=c;for(var u=2;u<o;u++)i[u]=n[u];return r.createElement.apply(null,i)}return r.createElement.apply(null,n)}g.displayName="MDXCreateElement"},4634:(e,t,n)=>{n.r(t),n.d(t,{assets:()=>s,contentTitle:()=>l,default:()=>d,frontMatter:()=>c,metadata:()=>u,toc:()=>p});var r=n(7462),a=n(3366),o=(n(7294),n(3905)),i=["components"],c={id:"using-caching",title:"Using query caching"},l=void 0,u={unversionedId:"querying/using-caching",id:"querying/using-caching",title:"Using query caching",description:"\x3c!--",source:"@site/docs/latest/querying/using-caching.md",sourceDirName:"querying",slug:"/querying/using-caching",permalink:"/docs/latest/querying/using-caching",draft:!1,tags:[],version:"current",frontMatter:{id:"using-caching",title:"Using query caching"},sidebar:"docs",previous:{title:"Query caching",permalink:"/docs/latest/querying/caching"},next:{title:"Query context",permalink:"/docs/latest/querying/query-context"}},s={},p=[{value:"Enabling query caching on Historicals",id:"enabling-query-caching-on-historicals",level:2},{value:"Enabling query caching on task executor services",id:"enabling-query-caching-on-task-executor-services",level:2},{value:"Enabling query caching on Brokers",id:"enabling-query-caching-on-brokers",level:2},{value:"Enabling caching in the query context",id:"enabling-caching-in-the-query-context",level:2},{value:"Learn more",id:"learn-more",level:2}],h={toc:p},g="wrapper";function d(e){var t=e.components,n=(0,a.Z)(e,i);return(0,o.kt)(g,(0,r.Z)({},h,n,{components:t,mdxType:"MDXLayout"}),(0,o.kt)("p",null,"This topic covers how to configure services to populate and use the Druid query caches. 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For information on how to configure the caching mechanism, see ",(0,o.kt)("a",{parentName:"p",href:"/docs/latest/configuration/#cache-configuration"},"Cache configuration"),"."),(0,o.kt)("p",null,"All query caches have a pair of parameters that control the way individual queries interact with the cache:"),(0,o.kt)("ul",null,(0,o.kt)("li",{parentName:"ul"},(0,o.kt)("inlineCode",{parentName:"li"},"useCache")," to instruct queries to use the cache for results."),(0,o.kt)("li",{parentName:"ul"},(0,o.kt)("inlineCode",{parentName:"li"},"populateCache")," to instruct a query to cache its results.")),(0,o.kt)("p",null,"The separation of concerns, usage and population, lets you include cached results for queries on uncommon data without polluting the cache with results that are unlikely to be reused by other queries, for example, large reports or queries on very old data."),(0,o.kt)("p",null,"To use caching, it must be enabled in the settings for the service to perform caching in the service's runtime properties. 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For example, to set the Broker to use and populate the whole-query cache for queries:"),(0,o.kt)("pre",null,(0,o.kt)("code",{parentName:"pre"},"druid.broker.cache.useResultLevelCache=true\ndruid.broker.cache.populateResultLevelCache=true\n")),(0,o.kt)("p",null,"See ",(0,o.kt)("a",{parentName:"p",href:"/docs/latest/configuration/#broker-caching"},"Broker caching")," for a description of all available Broker cache configurations."),(0,o.kt)("h2",{id:"enabling-caching-in-the-query-context"},"Enabling caching in the query context"),(0,o.kt)("p",null,"As long as the service is set to populate the cache, you can set cache options for individual queries in the query ",(0,o.kt)("a",{parentName:"p",href:"/docs/latest/querying/query-context"},"context"),". 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