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For information about functions available in SQL, refer to the\n",(0,i.kt)("a",{parentName:"p",href:"/docs/28.0.1/querying/sql-aggregations"},"SQL documentation"),".")),(0,i.kt)("p",null,"Post-aggregations are specifications of processing that should happen on aggregated values as they come out of Apache Druid. If you include a post aggregation as part of a query, make sure to include all aggregators the post-aggregator requires."),(0,i.kt)("p",null,"There are several post-aggregators available."),(0,i.kt)("h3",{id:"arithmetic-post-aggregator"},"Arithmetic post-aggregator"),(0,i.kt)("p",null,"The arithmetic post-aggregator applies the provided function to the given\nfields from left to right. The fields can be aggregators or other post aggregators."),(0,i.kt)("table",null,(0,i.kt)("thead",{parentName:"table"},(0,i.kt)("tr",{parentName:"thead"},(0,i.kt)("th",{parentName:"tr",align:null},"Property"),(0,i.kt)("th",{parentName:"tr",align:null},"Description"),(0,i.kt)("th",{parentName:"tr",align:null},"Required"))),(0,i.kt)("tbody",{parentName:"table"},(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"type")),(0,i.kt)("td",{parentName:"tr",align:null},"Must be ",(0,i.kt)("inlineCode",{parentName:"td"},'"arithmetic"'),"."),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"name")),(0,i.kt)("td",{parentName:"tr",align:null},"Output name of the post-aggregation"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"fn")),(0,i.kt)("td",{parentName:"tr",align:null},"Supported functions are ",(0,i.kt)("inlineCode",{parentName:"td"},"+"),", ",(0,i.kt)("inlineCode",{parentName:"td"},"-"),", ",(0,i.kt)("inlineCode",{parentName:"td"},"*"),", ",(0,i.kt)("inlineCode",{parentName:"td"},"/"),", ",(0,i.kt)("inlineCode",{parentName:"td"},"pow")," and ",(0,i.kt)("inlineCode",{parentName:"td"},"quotient")),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"fields")),(0,i.kt)("td",{parentName:"tr",align:null},"List of post-aggregator specs which define inputs to the ",(0,i.kt)("inlineCode",{parentName:"td"},"fn")),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"ordering")),(0,i.kt)("td",{parentName:"tr",align:null},"If no ordering (or ",(0,i.kt)("inlineCode",{parentName:"td"},"null"),") is specified, the default floating point ordering is used. ",(0,i.kt)("inlineCode",{parentName:"td"},"numericFirst")," ordering always returns finite values first, followed by ",(0,i.kt)("inlineCode",{parentName:"td"},"NaN"),", and infinite values last."),(0,i.kt)("td",{parentName:"tr",align:null},"No")))),(0,i.kt)("p",null,(0,i.kt)("strong",{parentName:"p"},"Note"),":"),(0,i.kt)("ul",null,(0,i.kt)("li",{parentName:"ul"},(0,i.kt)("inlineCode",{parentName:"li"},"/")," division always returns ",(0,i.kt)("inlineCode",{parentName:"li"},"0")," if dividing by",(0,i.kt)("inlineCode",{parentName:"li"},"0"),", regardless of the numerator."),(0,i.kt)("li",{parentName:"ul"},(0,i.kt)("inlineCode",{parentName:"li"},"quotient")," division behaves like regular floating point division"),(0,i.kt)("li",{parentName:"ul"},"Arithmetic post-aggregators always use floating point arithmetic.")),(0,i.kt)("p",null,"Example:"),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{\n "type" : "arithmetic",\n "name" : "mult",\n "fn" : "*",\n "fields": [\n {"type": "fieldAccess", "fieldName": "someAgg"},\n {"type": "fieldAccess", "fieldName": "someOtherAgg"}\n ]\n}\n')),(0,i.kt)("h3",{id:"field-accessor-post-aggregators"},"Field accessor post-aggregators"),(0,i.kt)("p",null,"These post-aggregators return the value produced by the specified ",(0,i.kt)("a",{parentName:"p",href:"/docs/28.0.1/querying/dimensionspecs"},"dimension")," or ",(0,i.kt)("a",{parentName:"p",href:"/docs/28.0.1/querying/aggregations"},"aggregator"),"."),(0,i.kt)("table",null,(0,i.kt)("thead",{parentName:"table"},(0,i.kt)("tr",{parentName:"thead"},(0,i.kt)("th",{parentName:"tr",align:null},"Property"),(0,i.kt)("th",{parentName:"tr",align:null},"Description"),(0,i.kt)("th",{parentName:"tr",align:null},"Required"))),(0,i.kt)("tbody",{parentName:"table"},(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"type")),(0,i.kt)("td",{parentName:"tr",align:null},"Must be ",(0,i.kt)("inlineCode",{parentName:"td"},'"fieldAccess"')," or ",(0,i.kt)("inlineCode",{parentName:"td"},'"finalizingFieldAccess"'),". Use type ",(0,i.kt)("inlineCode",{parentName:"td"},'"fieldAccess"')," to return the raw aggregation object, or use type ",(0,i.kt)("inlineCode",{parentName:"td"},'"finalizingFieldAccess"')," to return a finalized value, such as an estimated cardinality."),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"name")),(0,i.kt)("td",{parentName:"tr",align:null},"Output name of the post-aggregation"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes if defined as a standalone post-aggregation, but may be omitted if used inline to some other post-aggregator in a ",(0,i.kt)("inlineCode",{parentName:"td"},"fields")," list")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"fieldName")),(0,i.kt)("td",{parentName:"tr",align:null},"The output name of the dimension or aggregator to reference"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")))),(0,i.kt)("p",null,"Example:"),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{ "type" : "fieldAccess", "name": "someField", "fieldName" : "someAggregator" }\n')),(0,i.kt)("p",null,"or"),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{ "type" : "finalizingFieldAccess", "name": "someFinalizedField", "fieldName" : "someAggregator" }\n')),(0,i.kt)("h3",{id:"constant-post-aggregator"},"Constant post-aggregator"),(0,i.kt)("p",null,"The constant post-aggregator always returns the specified value."),(0,i.kt)("table",null,(0,i.kt)("thead",{parentName:"table"},(0,i.kt)("tr",{parentName:"thead"},(0,i.kt)("th",{parentName:"tr",align:null},"Property"),(0,i.kt)("th",{parentName:"tr",align:null},"Description"),(0,i.kt)("th",{parentName:"tr",align:null},"Required"))),(0,i.kt)("tbody",{parentName:"table"},(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"type")),(0,i.kt)("td",{parentName:"tr",align:null},"Must be ",(0,i.kt)("inlineCode",{parentName:"td"},'"constant"')),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"name")),(0,i.kt)("td",{parentName:"tr",align:null},"Output name of the post-aggregation"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"value")),(0,i.kt)("td",{parentName:"tr",align:null},"The constant value"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")))),(0,i.kt)("p",null,"Example:"),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{ "type" : "constant", "name" : "someConstant", "value" : 1234 }\n')),(0,i.kt)("h3",{id:"expression-post-aggregator"},"Expression post-aggregator"),(0,i.kt)("p",null,"The expression post-aggregator is defined using a Druid ",(0,i.kt)("a",{parentName:"p",href:"/docs/28.0.1/querying/math-expr"},"expression"),"."),(0,i.kt)("table",null,(0,i.kt)("thead",{parentName:"table"},(0,i.kt)("tr",{parentName:"thead"},(0,i.kt)("th",{parentName:"tr",align:null},"Property"),(0,i.kt)("th",{parentName:"tr",align:null},"Description"),(0,i.kt)("th",{parentName:"tr",align:null},"Required"))),(0,i.kt)("tbody",{parentName:"table"},(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"type")),(0,i.kt)("td",{parentName:"tr",align:null},"Must be ",(0,i.kt)("inlineCode",{parentName:"td"},'"expression"')),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"name")),(0,i.kt)("td",{parentName:"tr",align:null},"Output name of the post-aggregation"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"expression")),(0,i.kt)("td",{parentName:"tr",align:null},"Native Druid ",(0,i.kt)("a",{parentName:"td",href:"/docs/28.0.1/querying/math-expr"},"expression")," to compute, may refer to any dimension or aggregator output names"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"ordering")),(0,i.kt)("td",{parentName:"tr",align:null},"If no ordering (or ",(0,i.kt)("inlineCode",{parentName:"td"},"null"),') is specified, the "natural" ordering is used. 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If the expression produces array or complex types, specify ",(0,i.kt)("inlineCode",{parentName:"td"},"ordering")," as null and use ",(0,i.kt)("inlineCode",{parentName:"td"},"outputType")," instead to use the correct type native ordering."),(0,i.kt)("td",{parentName:"tr",align:null},"No")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"outputType")),(0,i.kt)("td",{parentName:"tr",align:null},"Output type is optional, and can be any native Druid type: ",(0,i.kt)("inlineCode",{parentName:"td"},"LONG"),", ",(0,i.kt)("inlineCode",{parentName:"td"},"FLOAT"),", ",(0,i.kt)("inlineCode",{parentName:"td"},"DOUBLE"),", ",(0,i.kt)("inlineCode",{parentName:"td"},"STRING"),", ",(0,i.kt)("inlineCode",{parentName:"td"},"ARRAY")," types (e.g. ",(0,i.kt)("inlineCode",{parentName:"td"},"ARRAY<LONG>"),"), or ",(0,i.kt)("inlineCode",{parentName:"td"},"COMPLEX")," types (e.g. ",(0,i.kt)("inlineCode",{parentName:"td"},"COMPLEX<json>"),"). 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If ",(0,i.kt)("inlineCode",{parentName:"td"},"outputType")," does not match the actual output type of the ",(0,i.kt)("inlineCode",{parentName:"td"},"expression"),", the value will be attempted to coerced to the specified type, possibly failing if coercion is not possible."),(0,i.kt)("td",{parentName:"tr",align:null},"No")))),(0,i.kt)("p",null,"Example:"),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{\n "type": "expression",\n "name": "someExpression",\n "expression": "someAgg + someOtherAgg",\n "ordering": null,\n "outputType": "LONG" \n}\n')),(0,i.kt)("h3",{id:"greatest--least-post-aggregators"},"Greatest / Least post-aggregators"),(0,i.kt)("p",null,(0,i.kt)("inlineCode",{parentName:"p"},"doubleGreatest")," and ",(0,i.kt)("inlineCode",{parentName:"p"},"longGreatest")," computes the maximum of all fields and Double.NEGATIVE_INFINITY.\n",(0,i.kt)("inlineCode",{parentName:"p"},"doubleLeast")," and ",(0,i.kt)("inlineCode",{parentName:"p"},"longLeast")," computes the minimum of all fields and Double.POSITIVE_INFINITY."),(0,i.kt)("table",null,(0,i.kt)("thead",{parentName:"table"},(0,i.kt)("tr",{parentName:"thead"},(0,i.kt)("th",{parentName:"tr",align:null},"Property"),(0,i.kt)("th",{parentName:"tr",align:null},"Description"),(0,i.kt)("th",{parentName:"tr",align:null},"Required"))),(0,i.kt)("tbody",{parentName:"table"},(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"type")),(0,i.kt)("td",{parentName:"tr",align:null},"Must be ",(0,i.kt)("inlineCode",{parentName:"td"},'"doubleGreatest"'),", ",(0,i.kt)("inlineCode",{parentName:"td"},'"doubleLeast"'),", ",(0,i.kt)("inlineCode",{parentName:"td"},'"longGreatest"'),", or ",(0,i.kt)("inlineCode",{parentName:"td"},'"longLeast"'),"."),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"name")),(0,i.kt)("td",{parentName:"tr",align:null},"Output name of the post-aggregation"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"fields")),(0,i.kt)("td",{parentName:"tr",align:null},"List of post-aggregator specs which define inputs to the greatest or least function"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")))),(0,i.kt)("p",null,"The difference between the ",(0,i.kt)("inlineCode",{parentName:"p"},"doubleMax")," aggregator and the ",(0,i.kt)("inlineCode",{parentName:"p"},"doubleGreatest")," post-aggregator is that ",(0,i.kt)("inlineCode",{parentName:"p"},"doubleMax")," returns the highest value of\nall rows for one specific column while ",(0,i.kt)("inlineCode",{parentName:"p"},"doubleGreatest")," returns the highest value of multiple columns in one row. These are similar to the\nSQL ",(0,i.kt)("inlineCode",{parentName:"p"},"MAX")," and ",(0,i.kt)("inlineCode",{parentName:"p"},"GREATEST")," functions."),(0,i.kt)("p",null,"Example:"),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{\n "type" : "doubleGreatest",\n "name" : "theGreatest",\n "fields": [\n { "type": "fieldAccess", "fieldName": "someAgg" },\n { "type": "fieldAccess", "fieldName": "someOtherAgg" }\n ]\n}\n')),(0,i.kt)("h3",{id:"javascript-post-aggregator"},"JavaScript post-aggregator"),(0,i.kt)("p",null,"Applies the provided JavaScript function to the given fields. Fields are passed as arguments to the JavaScript function in the given order."),(0,i.kt)("table",null,(0,i.kt)("thead",{parentName:"table"},(0,i.kt)("tr",{parentName:"thead"},(0,i.kt)("th",{parentName:"tr",align:null},"Property"),(0,i.kt)("th",{parentName:"tr",align:null},"Description"),(0,i.kt)("th",{parentName:"tr",align:null},"Required"))),(0,i.kt)("tbody",{parentName:"table"},(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"type")),(0,i.kt)("td",{parentName:"tr",align:null},"Must be ",(0,i.kt)("inlineCode",{parentName:"td"},'"javascript"')),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"name")),(0,i.kt)("td",{parentName:"tr",align:null},"Output name of the post-aggregation"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"fieldNames")),(0,i.kt)("td",{parentName:"tr",align:null},"List of input dimension or aggregator output names"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"function")),(0,i.kt)("td",{parentName:"tr",align:null},"String javascript function which accepts ",(0,i.kt)("inlineCode",{parentName:"td"},"fieldNames")," as arguments"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")))),(0,i.kt)("p",null,"Example:"),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{\n "type": "javascript",\n "name": "someJavascript",\n "fieldNames" : ["someAgg", "someOtherAgg"],\n "function": "function(someAgg, someOtherAgg) { return 100 * Math.abs(someAgg) / someOtherAgg;"\n}\n')),(0,i.kt)("admonition",{type:"info"},(0,i.kt)("p",{parentName:"admonition"}," JavaScript-based functionality is disabled by default. Please refer to the Druid ",(0,i.kt)("a",{parentName:"p",href:"/docs/28.0.1/development/javascript"},"JavaScript programming guide")," for guidelines about using Druid's JavaScript functionality, including instructions on how to enable it.")),(0,i.kt)("h3",{id:"hyperunique-cardinality-post-aggregator"},"HyperUnique Cardinality post-aggregator"),(0,i.kt)("p",null,"The hyperUniqueCardinality post aggregator is used to wrap a hyperUnique object such that it can be used in post aggregations."),(0,i.kt)("table",null,(0,i.kt)("thead",{parentName:"table"},(0,i.kt)("tr",{parentName:"thead"},(0,i.kt)("th",{parentName:"tr",align:null},"Property"),(0,i.kt)("th",{parentName:"tr",align:null},"Description"),(0,i.kt)("th",{parentName:"tr",align:null},"Required"))),(0,i.kt)("tbody",{parentName:"table"},(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"type")),(0,i.kt)("td",{parentName:"tr",align:null},"Must be ",(0,i.kt)("inlineCode",{parentName:"td"},'"hyperUniqueCardinality"')),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"name")),(0,i.kt)("td",{parentName:"tr",align:null},"Output name of the post-aggregation"),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")),(0,i.kt)("tr",{parentName:"tbody"},(0,i.kt)("td",{parentName:"tr",align:null},(0,i.kt)("inlineCode",{parentName:"td"},"fieldName")),(0,i.kt)("td",{parentName:"tr",align:null},"The output name of a ",(0,i.kt)("a",{parentName:"td",href:"/docs/28.0.1/querying/aggregations#cardinality-hyperunique"},(0,i.kt)("inlineCode",{parentName:"a"},"hyperUnique")," aggregator")),(0,i.kt)("td",{parentName:"tr",align:null},"Yes")))),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{\n "type" : "hyperUniqueCardinality",\n "name": "someCardinality",\n "fieldName" : "someHyperunique"\n}\n')),(0,i.kt)("p",null,"It can be used in a sample calculation as so:"),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{\n ...\n "aggregations" : [{\n {"type" : "count", "name" : "rows"},\n {"type" : "hyperUnique", "name" : "unique_users", "fieldName" : "uniques"}\n }],\n "postAggregations" : [{\n "type" : "arithmetic",\n "name" : "average_users_per_row",\n "fn" : "/",\n "fields" : [\n { "type" : "hyperUniqueCardinality", "fieldName" : "unique_users" },\n { "type" : "fieldAccess", "name" : "rows", "fieldName" : "rows" }\n ]\n }]\n ...\n')),(0,i.kt)("p",null,'This post-aggregator will inherit the rounding behavior of the aggregator it references. Note that this inheritance\nis only effective if you directly reference an aggregator. Going through another post-aggregator, for example, will\ncause the user-specified rounding behavior to get lost and default to "no rounding".'),(0,i.kt)("h2",{id:"example-usage"},"Example Usage"),(0,i.kt)("p",null,'In this example, let\u2019s calculate a simple percentage using post aggregators. Let\u2019s imagine our data set has a metric called "total".'),(0,i.kt)("p",null,"The format of the query JSON is as follows:"),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{\n ...\n "aggregations" : [\n { "type" : "count", "name" : "rows" },\n { "type" : "doubleSum", "name" : "tot", "fieldName" : "total" }\n ],\n "postAggregations" : [{\n "type" : "arithmetic",\n "name" : "average",\n "fn" : "/",\n "fields" : [\n { "type" : "fieldAccess", "name" : "tot", "fieldName" : "tot" },\n { "type" : "fieldAccess", "name" : "rows", "fieldName" : "rows" }\n ]\n }]\n ...\n}\n')),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{\n ...\n "aggregations" : [\n { "type" : "doubleSum", "name" : "tot", "fieldName" : "total" },\n { "type" : "doubleSum", "name" : "part", "fieldName" : "part" }\n ],\n "postAggregations" : [{\n "type" : "arithmetic",\n "name" : "part_percentage",\n "fn" : "*",\n "fields" : [\n { "type" : "arithmetic",\n "name" : "ratio",\n "fn" : "/",\n "fields" : [\n { "type" : "fieldAccess", "name" : "part", "fieldName" : "part" },\n { "type" : "fieldAccess", "name" : "tot", "fieldName" : "tot" }\n ]\n },\n { "type" : "constant", "name": "const", "value" : 100 }\n ]\n }]\n ...\n}\n')),(0,i.kt)("p",null,"The same could be computed using an expression post-aggregator: "),(0,i.kt)("pre",null,(0,i.kt)("code",{parentName:"pre",className:"language-json"},'{\n ...\n "aggregations" : [\n { "type" : "doubleSum", "name" : "tot", "fieldName" : "total" },\n { "type" : "doubleSum", "name" : "part", "fieldName" : "part" }\n ],\n "postAggregations" : [{\n "type" : "expression",\n "name" : "part_percentage",\n "expression" : "100 * (part / tot)"\n }]\n ...\n}\n')))}k.isMDXComponent=!0}}]); |