聚合查询
-
概念
聚合(aggs)不同于普通查询,是目前学到的第二种大的查询分类,第一种即“query”,因此在代码中的第一层嵌套由“query”变为了“aggs”。用于进行聚合的字段必须是exact value,分词字段不可进行聚合,对于text字段如果需要使用聚合,需要开启fielddata,但是通常不建议,因为fielddata是将聚合使用的数据结构由磁盘(doc_values)变为了堆内存(field_data),大数据的聚合操作很容易导致OOM,详细原理会在进阶篇中阐述。
-
聚合分类
- 分桶聚合(Bucket agregations):类比SQL中的group by的作用,主要用于统计不同类型数据的数量
- 指标聚合(Metrics agregations):主要用于最大值、最小值、平均值、字段之和等指标的统计
- 管道聚合(Pipeline agregations):用于对聚合的结果进行二次聚合,如要统计绑定数量最多的标签bucket,就是要先按照标签进行分桶,再在分桶的结果上计算最大值。
-
语法
GET product/_search { "aggs": { "<aggs_name>": { "<agg_type>": { "field": "<field_name>" } } } }
aggs_name:聚合函数的名称
agg_type:聚合种类,比如是桶聚合(terms)或者是指标聚合(avg、sum、min、max等)
field_name:字段名称或者叫域名。
-
桶聚合:
场景:用于统计不同种类的文档的数量,可进行嵌套统计。
函数:terms
注意:聚合字段必须是exact value,如keyword
-
指标聚合
场景:用于统计某个指标,如最大值、最小值、平均值,可以结合桶聚合一起使用,如按照商品类型分桶,统计每个桶的平均价格。
函数:平均值:Avg、最大值:Max、最小值:Min、求和:Sum、详细信息:Stats、数量:Value count
-
管道聚合
场景:用于对聚合查询的二次聚合,如统计平均价格最低的商品分类,即先按照商品分类进行桶聚合,并计算其平均价格,然后对其平均价格计算最小值聚合
函数:Min bucket:最小桶、Max bucket:最大桶、Avg bucket:桶平均值、Sum bucket:桶求和、Stats bucket:桶信息
注意:buckets_path为管道聚合的关键字,其值从当前聚合统计的聚合函数开始计算为第一级。比如下面例子中,my_aggs和my_min_bucket同级, my_aggs就是buckets_path值的起始值。
GET product/_search { "size": 0, "aggs": { "my_aggs": { "terms": { ... }, "aggs": { "my_price_bucket": { ... } } }, "my_min_bucket":{ "min_bucket": { "buckets_path": "my_aggs>price_bucket" } } } }
-
嵌套聚合
语法:文章来源:https://www.toymoban.com/news/detail-405778.html
GET product/_search { "size": 0, "aggs": { "<agg_name>": { "<agg_type>": { "field": "<field_name>" }, "aggs": { "<agg_name_child>": { "<agg_type>": { "field": "<field_name>" } } } } } }
用途:用于在某种聚合的计算结果之上再次聚合,如统计不同类型商品的平均价格,就是在按照商品类型桶聚合之后,在其结果之上计算平均价格
-
聚合和查询的相互关系
-
基于query或filter的聚合
语法:
GET product/_search { "query": { ... }, "aggs": { ... } }
注意:以上语法,执行顺序为先query后aggs,顺序和谁在上谁在下没有关系。query中可以是查询、也可以是filter、或者bool query
-
基于聚合结果的查询、
GET product/_search { "aggs": { ... }, "post_filter": { ... } }
注意:以上语法,执行顺序为先aggs后post_filter,顺序和谁在上谁在下没有关系。
-
查询条件的作用域
GET product/_search { "size": 10, "query": { ... }, "aggs": { "avg_price": { ... }, "all_avg_price": { "global": {}, "aggs": { ... } } } }
上面例子中,avg_price的计算结果是基于query的查询结果的,而all_avg_price的聚合是基于all data的
-
-
聚合排序
-
排序规则:
order_type:_count(数量) _key(聚合结果的key值) _term(废弃但是仍然可用,使用_key代替)
GET product/_search { "aggs": { "type_agg": { "terms": { "field": "tags", "order": { "<order_type>": "desc" }, "size": 10 } } } }
-
多级排序:即排序的优先级,按照外层优先的顺序
GET product/_search?size=0 { "aggs": { "first_sort": { ... "aggs": { "second_sort": { ... } } } } }
上例中,先按照first_sort排序,再按照second_sort排序
-
多层排序:即按照多层聚合中的里层某个聚合的结果进行排序
GET product/_search { "size": 0, "aggs": { "tag_avg_price": { "terms": { "field": "type.keyword", "order": { "agg_stats>my_stats.sum": "desc" } }, "aggs": { "agg_stats": { ... "aggs": { "my_stats": { "extended_stats": { ... } } } } } } } }
上例中,按照里层聚合“my_stats”进行排序
-
-
常用的查询函数
-
histogram:直方图或柱状图统计
用途:用于区间统计,如不同价格商品区间的销售情况
语法:
GET product/_search?size=0 { "aggs": { "<histogram_name>": { "histogram": { "field": "price", #字段名称 "interval": 1000, #区间间隔 "keyed": true, #返回数据的结构化类型 "min_doc_count": <num>, #返回桶的最小文档数阈值,即文档数小于num的桶不会被输出 "missing": 1999 #空值的替换值,即如果文档对应字段的值为空,则默认输出1999(参数值) } } } }
-
date-histogram:基于日期的直方图,比如统计一年每个月的销售额
语法:
GET product/_search?size=0 { "aggs": { "my_date_histogram": { "date_histogram": { "field": "createtime", #字段需为date类型 "<interval_type>": "month", #时间间隔的参数可选项 "format": "yyyy-MM", #日期的格式化输出 "extended_bounds": { #输出空桶 "min": "2020-01", "max": "2020-12" } } } } }
interval_type:时间间隔的参数可选项
fixed_interval:ms(毫秒)、s(秒)、 m(分钟)、h(小时)、d(天),注意单位需要带上具体的数值,如2d为两天。需要当心当单位过小,会 导致输出桶过多而导致服务崩溃。
calendar_interval:month、year
interval:(废弃,但是仍然可用)
-
percentile 百分位统计 或者 饼状图
计算结果为何为近似值。
-
percentiles:用于评估当前数值分布情况,比如99 percentile 是 1000 , 是指 99%的数值都在1000以内。常见的一个场景就是我们制定 SLA 的时候常说 99% 的请求延迟都在100ms 以内,这个时候你就可以用 99 percentile 来查一下,看一下 99 percenttile 的值如果在 100ms 以内,就代表SLA达标了。
语法:
GET product/_search?size=0 { "aggs": { "<percentiles_name>": { "percentiles": { "field": "price", "percents": [ percent1, #区间的数值,如5、10、30、50、99 即代表5%、10%、30%、50%、99%的数值分布 percent2, ... ] } } } }
-
percentile_ranks: percentile rank 其实就是percentiles的反向查询,比如我想看一下 1000、3000 在当前数值中处于哪一个范围内,你查一下它的 rank,发现是95,99,那么说明有95%的数值都在1000以内,99%的数值都在3000以内。文章来源地址https://www.toymoban.com/news/detail-405778.html
GET product/_search?size=0 { "aggs": { "<percentiles_name>": { "percentile_ranks": { "field": "<field_value>", "values": [ rank1, rank2, ... ] } } } }
-
-
示例
# 聚合查询
DELETE product
## 数据
PUT product
{
"mappings" : {
"properties" : {
"createtime" : {
"type" : "date"
},
"date" : {
"type" : "date"
},
"desc" : {
"type" : "text",
"fields" : {
"keyword" : {
"type" : "keyword",
"ignore_above" : 256
}
},
"analyzer":"ik_max_word"
},
"lv" : {
"type" : "text",
"fields" : {
"keyword" : {
"type" : "keyword",
"ignore_above" : 256
}
}
},
"name" : {
"type" : "text",
"analyzer":"ik_max_word",
"fields" : {
"keyword" : {
"type" : "keyword",
"ignore_above" : 256
}
}
},
"price" : {
"type" : "long"
},
"tags" : {
"type" : "text",
"fields" : {
"keyword" : {
"type" : "keyword",
"ignore_above" : 256
}
}
},
"type" : {
"type" : "text",
"fields" : {
"keyword" : {
"type" : "keyword",
"ignore_above" : 256
}
}
}
}
}
}
PUT /product/_doc/1
{
"name" : "小米手机",
"desc" : "手机中的战斗机",
"price" : 3999,
"lv":"旗舰机",
"type":"手机",
"createtime":"2020-10-01T08:00:00Z",
"tags": [ "性价比", "发烧", "不卡顿" ]
}
PUT /product/_doc/2
{
"name" : "小米NFC手机",
"desc" : "支持全功能NFC,手机中的滑翔机",
"price" : 4999,
"lv":"旗舰机",
"type":"手机",
"createtime":"2020-05-21T08:00:00Z",
"tags": [ "性价比", "发烧", "公交卡" ]
}
PUT /product/_doc/3
{
"name" : "NFC手机",
"desc" : "手机中的轰炸机",
"price" : 2999,
"lv":"高端机",
"type":"手机",
"createtime":"2020-06-20",
"tags": [ "性价比", "快充", "门禁卡" ]
}
PUT /product/_doc/4
{
"name" : "小米耳机",
"desc" : "耳机中的黄焖鸡",
"price" : 999,
"lv":"百元机",
"type":"耳机",
"createtime":"2020-06-23",
"tags": [ "降噪", "防水", "蓝牙" ]
}
PUT /product/_doc/5
{
"name" : "红米耳机",
"desc" : "耳机中的肯德基",
"price" : 399,
"type":"耳机",
"lv":"百元机",
"createtime":"2020-07-20",
"tags": [ "防火", "低音炮", "听声辨位" ]
}
PUT /product/_doc/6
{
"name" : "小米手机10",
"desc" : "充电贼快掉电更快,超级无敌望远镜,高刷电竞屏",
"price" : "",
"lv":"旗舰机",
"type":"手机",
"createtime":"2020-07-27",
"tags": [ "120HZ刷新率", "120W快充", "120倍变焦" ]
}
PUT /product/_doc/7
{
"name" : "挨炮 SE2",
"desc" : "除了CPU,一无是处",
"price" : "3299",
"lv":"旗舰机",
"type":"手机",
"createtime":"2020-07-21",
"tags": [ "割韭菜", "割韭菜", "割新韭菜" ]
}
PUT /product/_doc/8
{
"name" : "XS Max",
"desc" : "听说要出新款12手机了,终于可以换掉手中的4S了",
"price" : 4399,
"lv":"旗舰机",
"type":"手机",
"createtime":"2020-08-19",
"tags": [ "5V1A", "4G全网通", "大" ]
}
PUT /product/_doc/9
{
"name" : "小米电视",
"desc" : "70寸性价比只选,不要一万八,要不要八千八,只要两千九百九十八",
"price" : 2998,
"lv":"高端机",
"type":"耳机",
"createtime":"2020-08-16",
"tags": [ "巨馍", "家庭影院", "游戏" ]
}
PUT /product/_doc/10
{
"name" : "红米电视",
"desc" : "我比上边那个更划算,我也2998,我也70寸,但是我更好看",
"price" : 2999,
"type":"电视",
"lv":"高端机",
"createtime":"2020-08-28",
"tags": [ "大片", "蓝光8K", "超薄" ]
}
PUT /product/_doc/11
{
"name": "红米电视",
"desc": "我比上边那个更划算,我也2998,我也70寸,但是我更好看",
"price": 2998,
"type": "电视",
"lv": "高端机",
"createtime": "2020-08-28",
"tags": [
"大片",
"蓝光8K",
"超薄"
]
}
## 语法
GET product/_search
{
"aggs": {
"<aggs_name>": {
"<agg_type>": {
"field": "<field_name>"
}
}
}
}
## 桶聚合 例:统计不同标签的商品数量
GET product/_search
{
"aggs": {
"tag_bucket": {
"terms": {
"field": "tags.keyword"
}
}
}
}
## 不显示hits数据:size:0
GET product/_search
{
"size": 0,
"aggs": {
"tag_bucket": {
"terms": {
"field": "tags.keyword"
}
}
}
}
## 排序
GET product/_search
{
"size": 0,
"aggs": {
"tag_bucket": {
"terms": {
"field": "tags.keyword",
"size": 3,
"order": {
"_count": "desc"
}
}
}
}
}
## doc_values和field_data
GET product/_search
{
"size": 0,
"aggs": {
"tag_bucket": {
"terms": {
"field": "name"
}
}
}
}
GET product/_search
{
"size": 0,
"aggs": {
"tag_bucket": {
"terms": {
"field": "name.keyword"
}
}
}
}
POST product/_mapping
{
"properties": {
"name": {
"type": "text",
"analyzer": "ik_max_word",
"fielddata": true
}
}
}
GET product/_search
{
"size": 0,
"aggs": {
"tag_bucket": {
"terms": {
"size": 20,
"field": "name"
}
}
}
}
#*****************************************
## 指标聚合
## 例:最贵、最便宜和平均价格三个指标
GET product/_search
{
"size": 0,
"aggs": {
"max_price": {
"max": {
"field": "price"
}
},
"min_price": {
"min": {
"field": "price"
}
},
"avg_price": {
"avg": {
"field": "price"
}
}
}
}
## 单个聚合查询所有指标
GET product/_search
{
"size": 0,
"aggs": {
"price_stats": {
"stats": {
"field": "price"
}
}
}
}
##按照name去重的数量
GET product/_search
{
"size": 0,
"aggs": {
"type_count": {
"cardinality": {
"field": "name"
}
}
}
}
GET product/_search
{
"size": 0,
"aggs": {
"type_count": {
"cardinality": {
"field": "name.keyword"
}
}
}
}
##对type计算去重后数量
GET product/_search
{
"size": 0,
"aggs": {
"type_count": {
"cardinality": {
"field": "lv.keyword"
}
}
}
}
##*********************************************
## 管道聚合 二次聚合
## 例:统计平均价格最低的商品分类
GET product/_search
{
"size": 0,
"aggs": {
"type_bucket": {
"terms": {
"field": "type.keyword"
},
"aggs": {
"price_bucket": {
"avg": {
"field": "price"
}
}
}
},
"min_bucket":{
"min_bucket": {
"buckets_path": "type_bucket>price_bucket"
}
}
}
}
##=============================================
## 嵌套聚合
## 语法
GET product/_search
{
"size": 0,
"aggs": {
"<agg_name>": {
"<agg_type>": {
"field": "<field_name>"
},
"aggs": {
"<agg_name_child>": {
"<agg_type>": {
"field": "<field_name>"
}
}
}
}
}
}
# 例:统计不同类型商品的不同级别的数量
GET product/_search
{
"size": 0,
"aggs": {
"type_lv": {
"terms": {
"field": "type.keyword"
},
"aggs": {
"lv": {
"terms": {
"field": "lv.keyword"
}
}
}
}
}
}
#按照lv分桶 输出每个桶的具体价格信息
GET product/_search
{
"size": 0,
"aggs": {
"lv_price": {
"terms": {
"field": "lv.keyword"
},
"aggs": {
"price": {
"stats": {
"field": "price"
}
}
}
}
}
}
##结合了上面两个例子
##统计不同类型商品 不同档次的 价格信息 标签信息
GET product/_search
{
"size": 0,
"aggs": {
"type_agg": {
"terms": {
"field": "type.keyword"
},
"aggs": {
"lv_agg": {
"terms": {
"field": "lv.keyword"
},
"aggs": {
"price_stats": {
"stats": {
"field": "price"
}
},
"tags_buckets": {
"terms": {
"field": "tags.keyword"
}
}
}
}
}
}
}
}
## 统计每个商品类型中 不同档次分类商品中 平均价格最低的档次
GET product/_search
{
"size": 0,
"aggs": {
"type_bucket": {
"terms": {
"field": "type.keyword"
},
"aggs": {
"lv_bucket": {
"terms": {
"field": "lv.keyword"
},
"aggs": {
"price_avg": {
"avg": {
"field": "price"
}
}
}
},
"min_bucket": {
"min_bucket": {
"buckets_path": "lv_bucket>price_avg"
}
}
}
}
}
}
#======================================================
#基于查询结果的聚合
GET product/_search
{
"size": 0,
"query": {
"range": {
"price": {
"gte": 5000
}
}
},
"aggs": {
"tags_bucket": {
"terms": {
"field": "tags.keyword"
}
}
}
}
#基于filter的aggs
GET product/_search
{
"query": {
"constant_score": {
"filter": {
"range": {
"price": {
"gte": 5000
}
}
}
}
},
"aggs": {
"tags_bucket": {
"terms": {
"field": "tags.keyword"
}
}
}
}
GET product/_search
{
"query": {
"bool": {
"filter": {
"range": {
"price": {
"gte": 5000
}
}
}
}
},
"aggs": {
"tags_bucket": {
"terms": {
"field": "tags.keyword"
}
}
}
}
#基于聚合的查询
GET product/_search
{
"aggs": {
"tags_bucket": {
"terms": {
"field": "tags.keyword"
}
}
},
"post_filter": {
"term": {
"tags.keyword": "性价比"
}
}
}
#取消查询条件&&查询条件嵌套
## 例:最贵、最便宜和平均价格三个指标
GET product/_search
{
"size": 10,
"query": {
"range": {
"price": {
"gte": 4000
}
}
},
"aggs": {
"max_price": {
"max": {
"field": "price"
}
},
"min_price": {
"min": {
"field": "price"
}
},
"avg_price": {
"avg": {
"field": "price"
}
},
"all_avg_price": {
"global": {},
"aggs": {
"avg_price": {
"avg": {
"field": "price"
}
}
}
},
"muti_avg_price": {
"filter": {
"range": {
"price": {
"lte": 4500
}
}
},
"aggs": {
"avg_price": {
"avg": {
"field": "price"
}
}
}
}
}
}
#===============================================
#聚合排序_count _key _term
GET product/_search
{
"size": 0,
"aggs": {
"type_agg": {
"terms": {
"field": "tags",
"order": {
"_count": "desc"
},
"size": 10
}
}
}
}
#多级排序
GET product/_search?size=0
{
"aggs": {
"first_sort": {
"terms": {
"field": "type.keyword",
"order": {
"_count": "desc"
}
},
"aggs": {
"second_sort": {
"terms": {
"field": "lv.keyword",
"order": {
"_count": "asc"
}
}
}
}
}
}
}
#多层排序
GET product/_search
{
"size": 0,
"aggs": {
"tag_avg_price": {
"terms": {
"field": "type.keyword",
"order": {
"agg_stats>stats.sum": "desc"
}
},
"aggs": {
"agg_stats": {
"filter": {
"terms": {
"type.keyword": [
"耳机","手机","电视"
]
}
},
"aggs": {
"stats": {
"extended_stats": {
"field": "price"
}
}
}
}
}
}
}
}
#===========================================================
# 常用的查询函数
## histogram 直方图 或者 柱状图
GET product/_search
{
"aggs": {
"price_range": {
"range": {
"field": "price",
"ranges": [
{
"from": 0,
"to": 1000
},
{
"from": 1000,
"to": 2000
},
{
"from": 3000,
"to": 4000
},
{
"from": 4000,
"to": 5000
}
]
}
}
}
}
GET product/_search?size=0
{
"aggs": {
"price_range": {
"range": {
"field": "createtime",
"ranges": [
{
"from": "2020-05-01",
"to": "2020-05-31"
},
{
"from": "2020-06-01",
"to": "2020-06-30"
},
{
"from": "2020-07-01",
"to": "2020-07-31"
},
{
"from": "2020-08-01"
}
]
}
}
}
}
#空值的处理逻辑 对字段的空值赋予默认值
GET product/_search?size=0
{
"aggs": {
"price_histogram": {
"histogram": {
"field": "price",
"interval": 1000,
"keyed": true,
"min_doc_count": 0,
"missing": 1999
}
}
}
}
#date-histogram
#ms s m h d
GET product/_search?size=0
{
"aggs": {
"my_date_histogram": {
"date_histogram": {
"field": "createtime",
"calendar_interval": "month",
"min_doc_count": 0,
"format": "yyyy-MM",
"extended_bounds": {
"min": "2020-01",
"max": "2020-12"
},
"order": {
"_count": "desc"
}
}
}
}
}
GET product/_search?size=0
{
"aggs": {
"my_auto_histogram": {
"auto_date_histogram": {
"field": "createtime",
"format": "yyyy-MM-dd",
"buckets": 180
}
}
}
}
#cumulative_sum
GET product/_search?size=0
{
"aggs": {
"my_date_histogram": {
"date_histogram": {
"field": "createtime",
"calendar_interval": "month",
"min_doc_count": 0,
"format": "yyyy-MM",
"extended_bounds": {
"min": "2020-01",
"max": "2020-12"
}
},
"aggs": {
"sum_agg": {
"sum": {
"field": "price"
}
},
"my_cumulative_sum":{
"cumulative_sum": {
"buckets_path": "sum_agg"
}
}
}
}
}
}
## percentile 百分位统计 或者 饼状图
## https://www.elastic.co/guide/en/elasticsearch/reference/7.10/search-aggregations-metrics-percentile-aggregation.html
GET product/_search?size=0
{
"aggs": {
"price_percentiles": {
"percentiles": {
"field": "price",
"percents": [
1,
5,
25,
50,
75,
95,
99
]
}
}
}
}
#percentile_ranks
#TDigest
GET product/_search?size=0
{
"aggs": {
"price_percentiles": {
"percentile_ranks": {
"field": "price",
"values": [
1000,
2000,
3000,
4000,
5000,
6000
]
}
}
}
}
到了这里,关于es-06聚合查询的文章就介绍完了。如果您还想了解更多内容,请在右上角搜索TOY模板网以前的文章或继续浏览下面的相关文章,希望大家以后多多支持TOY模板网!