文章目录



1. Bucket & Metric Aggregation

  • Metric 一些系列的统计方法
  • Bucket 一组满足条件的文档
    Elasticsearch Bucket & Metric 聚合分析及嵌套聚合_字段

2. Aggregation 的语法

Aggregation 属于 Search 的一部分。一般情况下,建议将其 Size 指定为 0
Elasticsearch Bucket & Metric 聚合分析及嵌套聚合_elasticsearch_02
demo
Elasticsearch Bucket & Metric 聚合分析及嵌套聚合_elasticsearch_03

3. Mertric Aggregation

单值分析:只输出一个分析结果

  • ​min,max,avg,sum​
  • ​Cardinality​​(类似 distinct Count)

多值分析:输出多个分析结果

  • ​stats ,extended stats​
  • ​percentile, percentile rank​
  • ​top hits​​ (排在前面的示例)

3.1 Metric 聚合的具体 Demo

查看最低工资
查看最高工资
一个聚合输出多个值
一次查询包含多个聚合

  • 同时查看最低 最高 和平均工资
DELETE /employees
#做一个员工表的定义
PUT /employees/
{
"mappings" : {
"properties" : {
"age" : {
"type" : "integer"
},
"gender" : {
"type" : "keyword"
},
"job" : {
"type" : "text",
"fields" : {
"keyword" : {
"type" : "keyword",
"ignore_above" : 50
}
}
},
"name" : {
"type" : "keyword"
},
"salary" : {
"type" : "integer"
}
}
}
}

插入数据

PUT /employees/_bulk
{ "index" : { "_id" : "1" } }
{ "name" : "Emma","age":32,"job":"Product Manager","gender":"female","salary":35000 }
{ "index" : { "_id" : "2" } }
{ "name" : "Underwood","age":41,"job":"Dev Manager","gender":"male","salary": 50000}
{ "index" : { "_id" : "3" } }
{ "name" : "Tran","age":25,"job":"Web Designer","gender":"male","salary":18000 }
{ "index" : { "_id" : "4" } }
{ "name" : "Rivera","age":26,"job":"Web Designer","gender":"female","salary": 22000}
{ "index" : { "_id" : "5" } }
{ "name" : "Rose","age":25,"job":"QA","gender":"female","salary":18000 }
{ "index" : { "_id" : "6" } }
{ "name" : "Lucy","age":31,"job":"QA","gender":"female","salary": 25000}
{ "index" : { "_id" : "7" } }
{ "name" : "Byrd","age":27,"job":"QA","gender":"male","salary":20000 }
{ "index" : { "_id" : "8" } }
{ "name" : "Foster","age":27,"job":"Java Programmer","gender":"male","salary": 20000}
{ "index" : { "_id" : "9" } }
{ "name" : "Gregory","age":32,"job":"Java Programmer","gender":"male","salary":22000 }
{ "index" : { "_id" : "10" } }
{ "name" : "Bryant","age":20,"job":"Java Programmer","gender":"male","salary": 9000}
{ "index" : { "_id" : "11" } }
{ "name" : "Jenny","age":36,"job":"Java Programmer","gender":"female","salary":38000 }
{ "index" : { "_id" : "12" } }
{ "name" : "Mcdonald","age":31,"job":"Java Programmer","gender":"male","salary": 32000}
{ "index" : { "_id" : "13" } }
{ "name" : "Jonthna","age":30,"job":"Java Programmer","gender":"female","salary":30000 }
{ "index" : { "_id" : "14" } }
{ "name" : "Marshall","age":32,"job":"Javascript Programmer","gender":"male","salary": 25000}
{ "index" : { "_id" : "15" } }
{ "name" : "King","age":33,"job":"Java Programmer","gender":"male","salary":28000 }
{ "index" : { "_id" : "16" } }
{ "name" : "Mccarthy","age":21,"job":"Javascript Programmer","gender":"male","salary": 16000}
{ "index" : { "_id" : "17" } }
{ "name" : "Goodwin","age":25,"job":"Javascript Programmer","gender":"male","salary": 16000}
{ "index" : { "_id" : "18" } }
{ "name" : "Catherine","age":29,"job":"Javascript Programmer","gender":"female","salary": 20000}
{ "index" : { "_id" : "19" } }
{ "name" : "Boone","age":30,"job":"DBA","gender":"male","salary": 30000}
{ "index" : { "_id" : "20" } }
{ "name" : "Kathy","age":29,"job":"DBA","gender":"female","salary": 20000}

3.2 Metric 聚合,找到最低的工资

POST employees/_search
{
"size": 0,
"aggs": {
"min_salary": {
"min": {
"field":"salary"
}
}
}
}
返回输出:
{
"took" : 943,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"min_salary" : {
"value" : 9000.0
}
}
}

3.3 Metric 聚合,找到最高的工资

POST employees/_search
{
"size": 0,
"aggs": {
"max_salary": {
"max": {
"field":"salary"
}
}
}
}
返回输出:
{
"took" : 2,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"max_salary" : {
"value" : 50000.0
}
}
}

3.4 多个 Metric 聚合,找到最低最高和平均工资

POST employees/_search
{
"size": 0,
"aggs": {
"max_salary": {
"max": {
"field": "salary"
}
},
"min_salary": {
"min": {
"field": "salary"
}
},
"avg_salary": {
"avg": {
"field": "salary"
}
}
}
}

返回输出:
{
"took" : 6,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"max_salary" : {
"value" : 50000.0
},
"avg_salary" : {
"value" : 24700.0
},
"min_salary" : {
"value" : 9000.0
}
}
}

3.5 一个聚合,输出多值

POST employees/_search
{
"size": 0,
"aggs": {
"stats_salary": {
"stats": {
"field":"salary"
}
}
}
}

返回输出:
{
"took" : 5,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"stats_salary" : {
"count" : 20,
"min" : 9000.0,
"max" : 50000.0,
"avg" : 24700.0,
"sum" : 494000.0
}
}
}

4. bucket Aggregation

按照一定的规则,将文档分配到不同的桶中,从而达到分类的目的。ES 提供的一些常见的 Bucket Aggregation

  • ​Term​
  • 数字类型:​​Range 、Date Range、Histogram / Data Histogram​

支持嵌套:也就在桶里在做分桶
Elasticsearch Bucket & Metric 聚合分析及嵌套聚合_java_04

4.1 Terms Aggregation

字段需要打开 fielddata,才能进行 Terms Aggregation

  • Keyword 默认支持​​doc_values​
  • Text 需要在 Mapping 中 enable ,会按照分词后的结果进行分

Demo

  • 对 job 和 job.keyword 进行聚合
  • 对性别进行 Terms 聚合
  • 指定 bucket size

4.2 对keword 进行聚合

POST employees/_search
{
"size": 0,
"aggs": {
"jobs": {
"terms": {
"field":"job.keyword"
}
}
}
}
返回输出:

{
"took" : 12,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"jobs" : {
"doc_count_error_upper_bound" : 0,
"sum_other_doc_count" : 0,
"buckets" : [
{
"key" : "Java Programmer",
"doc_count" : 7
},
{
"key" : "Javascript Programmer",
"doc_count" : 4
},
{
"key" : "QA",
"doc_count" : 3
},
{
"key" : "DBA",
"doc_count" : 2
},
{
"key" : "Web Designer",
"doc_count" : 2
},
{
"key" : "Dev Manager",
"doc_count" : 1
},
{
"key" : "Product Manager",
"doc_count" : 1
}
]
}
}
}

4.3 对 Text 字段进行 terms 聚合查询,失败

POST employees/_search
{
"size": 0,
"aggs": {
"jobs": {
"terms": {
"field":"job"
}
}
}
}

返回输出:
{
"error": {
"root_cause": [
{
"type": "illegal_argument_exception",
"reason": "Fielddata is disabled on text fields by default. Set fielddata=true on [job] in order to load fielddata in memory by uninverting the inverted index. Note that this can however use significant memory. Alternatively use a keyword field instead."
}
],
"type": "search_phase_execution_exception",
"reason": "all shards failed",
"phase": "query",
"grouped": true,
"failed_shards": [
{
"shard": 0,
"index": "employees",
"node": "tPL1-C2IT6-eVbv5FfEWlg",
"reason": {
"type": "illegal_argument_exception",
"reason": "Fielddata is disabled on text fields by default. Set fielddata=true on [job] in order to load fielddata in memory by uninverting the inverted index. Note that this can however use significant memory. Alternatively use a keyword field instead."
}
}
],
"caused_by": {
"type": "illegal_argument_exception",
"reason": "Fielddata is disabled on text fields by default. Set fielddata=true on [job] in order to load fielddata in memory by uninverting the inverted index. Note that this can however use significant memory. Alternatively use a keyword field instead.",
"caused_by": {
"type": "illegal_argument_exception",
"reason": "Fielddata is disabled on text fields by default. Set fielddata=true on [job] in order to load fielddata in memory by uninverting the inverted index. Note that this can however use significant memory. Alternatively use a keyword field instead."
}
}
},
"status": 400
}

4.4 对 Text 字段打开 fielddata,支持terms aggregation

PUT employees/_mapping
{
"properties" : {
"job":{
"type": "text",
"fielddata": true
}
}
}

4.5 对 Text 字段进行 terms 分词。分词后的terms

POST employees/_search
{
"size": 0,
"aggs": {
"jobs": {
"terms": {
"field":"job"
}
}
}
}

返回输出:
{
"took" : 1,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"jobs" : {
"doc_count_error_upper_bound" : 0,
"sum_other_doc_count" : 0,
"buckets" : [
{
"key" : "programmer",
"doc_count" : 11
},
{
"key" : "java",
"doc_count" : 7
},
{
"key" : "javascript",
"doc_count" : 4
},
{
"key" : "qa",
"doc_count" : 3
},
{
"key" : "dba",
"doc_count" : 2
},
{
"key" : "designer",
"doc_count" : 2
},
{
"key" : "manager",
"doc_count" : 2
},
{
"key" : "web",
"doc_count" : 2
},
{
"key" : "dev",
"doc_count" : 1
},
{
"key" : "product",
"doc_count" : 1
}
]
}
}
}



POST employees/_search
{
"size": 0,
"aggs": {
"jobs": {
"terms": {
"field":"job.keyword"
}
}
}
}

返回输出:
{
"took" : 0,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"jobs" : {
"doc_count_error_upper_bound" : 0,
"sum_other_doc_count" : 0,
"buckets" : [
{
"key" : "Java Programmer",
"doc_count" : 7
},
{
"key" : "Javascript Programmer",
"doc_count" : 4
},
{
"key" : "QA",
"doc_count" : 3
},
{
"key" : "DBA",
"doc_count" : 2
},
{
"key" : "Web Designer",
"doc_count" : 2
},
{
"key" : "Dev Manager",
"doc_count" : 1
},
{
"key" : "Product Manager",
"doc_count" : 1
}
]
}
}
}

4.6 对job.keyword 和 job 进行 terms 聚合,分桶的总数并不一样

POST employees/_search
{
"size": 0,
"aggs": {
"cardinate": {
"cardinality": {
"field": "job"
}
}
}
}

返回输出:
{
"took" : 30,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"cardinate" : {
"value" : 10
}
}
}
POST employees/_search
{
"size": 0,
"aggs": {
"cardinate": {
"cardinality": {
"field": "job。keyword"
}
}
}
}

返回输出:
{
"took" : 5,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"cardinate" : {
"value" : 0
}
}
}

4.7 对性别的 keyword 进行聚合

POST employees/_search
{
"size": 0,
"aggs": {
"gender": {
"terms": {
"field":"gender"
}
}
}
}


返回输出:
{
"took" : 2,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"gender" : {
"doc_count_error_upper_bound" : 0,
"sum_other_doc_count" : 0,
"buckets" : [
{
"key" : "male",
"doc_count" : 12
},
{
"key" : "female",
"doc_count" : 8
}
]
}
}
}

4.8 指定 bucket 的 size

POST employees/_search
{
"size": 0,
"aggs": {
"ages_5": {
"terms": {
"field":"age",
"size":3
}
}
}
}

返回输出:
{
"took" : 4,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"ages_5" : {
"doc_count_error_upper_bound" : 0,
"sum_other_doc_count" : 12,
"buckets" : [
{
"key" : 25,
"doc_count" : 3
},
{
"key" : 32,
"doc_count" : 3
},
{
"key" : 27,
"doc_count" : 2
}
]
}
}
}

4.9 指定size,不同工种中,年纪最大的3个员工的具体信息

POST employees/_search
{
"size": 0,
"aggs": {
"jobs": {
"terms": {
"field":"job.keyword"
},
"aggs":{
"old_employee":{
"top_hits":{
"size":3,
"sort":[
{
"age":{
"order":"desc"
}
}
]
}
}
}
}
}
}

4.10 优化Terms聚合性能

Elasticsearch Bucket & Metric 聚合分析及嵌套聚合_java_05

5. Range & Histogram聚合

5.1 Salary Ranges 分桶,可以自己定义 key

POST employees/_search
{
"size": 0,
"aggs": {
"salary_range": {
"range": {
"field":"salary",
"ranges":[
{
"to":10000
},
{
"from":10000,
"to":20000
},
{
"key":">20000",
"from":20000
}
]
}
}
}
}

返回输出:

{
"took" : 9,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : {
"value" : 20,
"relation" : "eq"
},
"max_score" : null,
"hits" : [ ]
},
"aggregations" : {
"salary_range" : {
"buckets" : [
{
"key" : "*-10000.0",
"to" : 10000.0,
"doc_count" : 1
},
{
"key" : "10000.0-20000.0",
"from" : 10000.0,
"to" : 20000.0,
"doc_count" : 4
},
{
"key" : ">20000",
"from" : 20000.0,
"doc_count" : 15
}
]
}
}
}

5.2 Salary Histogram,工资0到10万,以 5000一个区间进行分桶

POST employees/_search
{
"size": 0,
"aggs": {
"salary_histrogram": {
"histogram": {
"field":"salary",
"interval":5000,
"extended_bounds":{
"min":0,
"max":100000

}
}
}
}
}

5.3 嵌套聚合1,按照工作类型分桶,并统计工资信息

POST employees/_search
{
"size": 0,
"aggs": {
"Job_salary_stats": {
"terms": {
"field": "job.keyword"
},
"aggs": {
"salary": {
"stats": {
"field": "salary"
}
}
}
}
}
}

Elasticsearch Bucket & Metric 聚合分析及嵌套聚合_字段_06

5.4 多次嵌套。根据工作类型分桶,然后按照性别分桶,计算工资的统计信息

POST employees/_search
{
"size": 0,
"aggs": {
"Job_gender_stats": {
"terms": {
"field": "job.keyword"
},
"aggs": {
"gender_stats": {
"terms": {
"field": "gender"
},
"aggs": {
"salary_stats": {
"stats": {
"field": "salary"
}
}
}
}
}
}
}
}

Elasticsearch Bucket & Metric 聚合分析及嵌套聚合_字段_07