# 執行聚合
聚合提供了分組并統計數據的能力。理解聚合的最簡單的方式是將其粗略地等同為SQL的GROUP BY和SQL聚合函數。在Elasticsearch中,你可以在一個響應中同時返回命中的數據和聚合結果。你可以使用簡單的API同時運行查詢和多個聚合并一次返回,這避免了來回的網絡通信,是非常強大和高效的。
首先,這個例子演示了根據賬戶所在的州來統計各個州的賬戶數,并返回賬戶數最多的前10個州(默認大小為10):
```
GET /bank/_search
{
"size": 0,
"aggs": {
"group_by_state": {
"terms": {
"field": "state.keyword"
}
}
}
}
```
在SQL中,上面的聚合在概念上類似于:
```
SELECT COUNT(*) from bank GROUP BY state ORDER BY COUNT(*) DESC
```
響應(其中一部分)是:
```
{
"took": 29,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits" : {
"total" : 1000,
"max_score" : 0.0,
"hits" : [ ]
},
"aggregations" : {
"group_by_state" : {
"doc_count_error_upper_bound": 20,
"sum_other_doc_count": 770,
"buckets" : [ {
"key" : "ID",
"doc_count" : 27
}, {
"key" : "TX",
"doc_count" : 27
}, {
"key" : "AL",
"doc_count" : 25
}, {
"key" : "MD",
"doc_count" : 25
}, {
"key" : "TN",
"doc_count" : 23
}, {
"key" : "MA",
"doc_count" : 21
}, {
"key" : "NC",
"doc_count" : 21
}, {
"key" : "ND",
"doc_count" : 21
}, {
"key" : "ME",
"doc_count" : 20
}, {
"key" : "MO",
"doc_count" : 20
} ]
}
}
}
```
我們可以看到`ID`(Idaho)州有27個賬戶,緊跟著`TX`(Texas)州有27個賬戶、`AL`(Alabama)有25個賬戶,依此類推。
注意我們將`size`設置成 0,這樣我們就可以只看到聚合結果了,而不會顯示命中的文檔的詳細結果。
在先前聚合的基礎上,現在這個例子計算了每個州的賬戶的平均存款(還是按照賬戶數量倒序排序的前10個州):
```
GET /bank/_search
{
"size": 0,
"aggs": {
"group_by_state": {
"terms": {
"field": "state.keyword"
},
"aggs": {
"average_balance": {
"avg": {
"field": "balance"
}
}
}
}
}
}
```
注意, 我們把`average_balance`聚合嵌套在了`group_by_state`聚合之中。這是所有聚合的一個常用模式。你可以在任意的聚合之中嵌套聚合,這樣就可以從你的數據中抽取出想要的結果。
在前面的聚合的基礎上,現在讓我們按照平均余額進行排序:
```
GET /bank/_search
{
"size": 0,
"aggs": {
"group_by_state": {
"terms": {
"field": "state.keyword",
"order": {
"average_balance": "desc"
}
},
"aggs": {
"average_balance": {
"avg": {
"field": "balance"
}
}
}
}
}
}
```
下面的例子顯示了如何使用年齡段(20-29,30-39,40-49)分組,然后再用性別分組,最后為每一個年齡段的每組性別計算平均賬戶余額。
```
GET /bank/_search
{
"size": 0,
"aggs": {
"group_by_age": {
"range": {
"field": "age",
"ranges": [
{
"from": 20,
"to": 30
},
{
"from": 30,
"to": 40
},
{
"from": 40,
"to": 50
}
]
},
"aggs": {
"group_by_gender": {
"terms": {
"field": "gender.keyword"
},
"aggs": {
"average_balance": {
"avg": {
"field": "balance"
}
}
}
}
}
}
}
}
```
There are many other aggregations capabilities that we won’t go into detail here. The [aggregations reference guide](https://www.elastic.co/guide/en/elasticsearch/reference/6.0/search-aggregations.html) is a great starting point if you want to do further experimentation.
- 入門
- 基本概念
- 安裝
- 探索你的集群
- 集群健康
- 列出所有索引庫
- 創建一個索引庫
- 索引文檔創建與查詢
- 刪除一個索引庫
- 修改你的數據
- 更新文檔
- 刪除文檔
- 批量處理
- 探索你的數據
- 搜索API
- 查詢語言介紹
- 執行搜索
- 執行過濾
- 執行聚合
- 總結
- Elasticsearch設置
- 安裝Elasticsearch
- .zip或.tar.gz文件的安裝方式
- Install Elasticsearch with .zip on Windows
- Debian軟件包安裝方式
- RPM安裝方式
- Install Elasticsearch with Windows MSI Installer
- Docker安裝方式
- 配置Elasticsearch
- 安全配置
- 日志配置
- 重要的Elasticsearch配置
- 重要的系統配置
- 系統設置
- 在jvm.options中設置JVM堆大小
- 禁用swapping
- 文件描述符
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- 線程數
- DNS cache settings
- 啟動前檢查
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- Max file size check
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- Early-access check
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- Elasticsearch停機
- Elasticsearch升級
- 滾動升級
- 全集群重啟升級
- 索引重建升級
- Set up X-Pack
- Installing X-Pack
- X-Pack Settings
- Watcher Settings
- Configuring Security
- Breaking changes in 6.0
- X-Pack Breaking Changes
- 重大變化
- 6.0的重大變化
- 聚合變化
- Cat API變化
- 客戶端變化
- 集群變化
- 文檔API變化
- 索引變化
- 預處理變化
- 映射變化
- Packaging變化
- Percolator變化
- 插件變化
- 索引重建變化
- 信息統計變化
- DSL查詢變化
- 設置變化
- 腳本變化
- API約定
- 多索引語法
- 索引庫名稱的日期運算
- 常用選項
- URL-based訪問控制
- 文檔APIs
- 讀寫文檔
- 索引接口
- Get接口
- Delete API
- Delete By Query API
- Update API
- Update By Query API
- Multi Get API
- Bulk API
- Reindex API
- Term Vectors
- Multi termvectors API
- ?refresh
- 搜索APIs
- Search
- URI Search
- Request Body Search
- Query
- From / Size
- Sort
- Source filtering
- Fields
- Script Fields
- Doc value Fields
- Post filter
- Highlighting
- Rescoring
- Search Type
- Scroll
- Preference
- Explain
- Version
- Index Boost
- min_score
- Named Queries
- Inner hits
- Field Collapsing
- Search After
- Search Template
- Multi Search Template
- Search Shards API
- Suggesters
- Term suggester
- Phrase Suggester
- Completion Suggester
- Context Suggester
- Returning the type of the suggester
- Multi Search API
- Count API
- Validate API
- Explain API
- Profile API
- Profiling Queries
- Profiling Aggregations
- Profiling Considerations
- Field Capabilities API
- Aggregations
- Metrics Aggregations
- 平均值聚合
- 值計數聚合(Value Count Aggregation)
- Cardinality Aggregation
- Extended Stats Aggregation
- 地理邊界聚合
- 地理重心聚合
- Max Aggregation
- Min Aggregation
- Percentiles Aggregation
- Percentile Ranks Aggregation
- Scripted Metric Aggregation
- Stats Aggregation
- Sum Aggregation
- Top hits Aggregation
- Value Count Aggregation
- Bucket Aggregations
- 鄰接矩陣聚合
- Children Aggregation
- Date Histogram Aggregation
- Date Range Aggregation
- Significant Terms Aggregation
- Filter Aggregation(過濾器聚合)
- Filters Aggregation
- Geo Distance Aggregation(地理距離聚合) 轉至元數據結尾
- GeoHash grid Aggregation(GeoHash網格聚合)
- Global Aggregation(全局聚合) 轉至元數據結尾
- Histogram Aggregation
- IP Range Aggregation(IP范圍聚合)
- Missing Aggregation
- Nested Aggregation(嵌套聚合)
- Range Aggregation(范圍聚合)
- Reverse nested Aggregation
- Sampler Aggregation
- Significant Terms Aggregation
- Significant Text Aggregation
- Terms Aggregation
- Pipeline Aggregations
- Avg Bucket Aggregation
- Derivative Aggregation(導數聚合)
- Max Bucket Aggregation
- Min Bucket Aggregation
- Sum Bucket Aggregation
- Stats Bucket Aggregation
- Extended Stats Bucket Aggregation(擴展信息桶聚合)
- Percentiles Bucket Aggregation(百分數桶聚合)
- Moving Average Aggregation
- Cumulative Sum Aggregation(累積匯總聚合)
- Bucket Script Aggregation(桶腳本聚合)
- Bucket Selector Aggregation(桶選擇器聚合)
- Serial Differencing Aggregation(串行差異聚合)
- Matrix Aggregations
- Matrix Stats
- Caching heavy aggregations
- Returning only aggregation results
- Aggregation Metadata
- Returning the type of the aggregation
- Indices APIs
- Create Index /創建索引
- Delete Index /刪除索引
- Get Index /獲取索引
- Indices Exists /索引存在
- Open / Close Index API /啟動關閉索引
- Shrink Index /縮小索引
- Rollover Index/滾動索引
- Put Mapping /提交映射
- Get Mapping /獲取映射
- Get Field Mapping /獲取字段映射
- Types Exists
- Index Aliases
- Update Indices Settings
- Get Settings
- Analyze
- Explain Analyze
- Index Templates
- 索引統計信息
- 索引段
- 索引恢復
- 索引分片存儲
- 清理緩存
- 刷新
- 同步刷新
- 重新加載
- 強制合并
- Cat APIs
- cat aliases
- cat allocation
- cat count
- cat fielddata
- cat health
- cat indices
- cat master
- cat nodeattrs
- cat nodes
- cat pending tasks
- cat plugins
- cat recovery
- cat repositories
- cat segments
- cat shards
- cat thread pool
- cat snapshots
- cat templates
- Cluster APIs
- 集群健康
- 集群狀態
- 集群統計
- 掛起的集群任務
- 集群重新路由
- Cluster Update Settings
- Nodes Stats
- Nodes Info
- Nodes Feature Usage
- Remote Cluster Info
- Task Management API
- Nodes hot_threads
- Cluster Allocation Explain API
- Query DSL
- 查詢context與過濾context
- Match All Query
- 全文搜索
- 匹配查詢
- 短語匹配查詢
- 短語前綴匹配查詢
- 多字段查詢
- 常用術語查詢
- 查詢語句查詢
- 簡單查詢語句
- Term level queries
- Term Query
- Terms Query
- Range Query
- Exists Query
- Prefix Query
- Wildcard Query
- Regexp Query
- Fuzzy Query
- Type Query
- Ids Query
- 復合查詢
- Constant Score 查詢
- Bool 查詢
- Dis Max 查詢
- Function Score 查詢
- Boosting 查詢
- Joining queries
- Has Child Query
- Has Parent Query
- Nested Query(嵌套查詢)
- Parent Id Query
- Geo queries
- GeoShape Query(地理形狀查詢)
- Geo Bounding Box Query(地理邊框查詢)
- Geo Distance Query(地理距離查詢)
- Geo Polygon Query(地理多邊形查詢)
- Specialized queries
- More Like This Query
- Script Query
- Percolate Query
- Span queries
- Span Term 查詢
- Span Multi Term 查詢
- Span First 查詢
- Span Near 查詢
- Span Or 查詢
- Span Not 查詢
- Span Containing 查詢
- Span Within 查詢
- Span Field Masking 查詢 轉至元數據結尾
- Minimum Should Match
- Multi Term Query Rewrite
- Mapping
- Removal of mapping types
- Field datatypes
- Array
- Binary
- Range
- Boolean
- Date
- Geo-point datatype
- Geo-Shape datatype
- IP datatype
- Keyword datatype
- Nested datatype
- Numeric datatypes
- Object datatype
- Text
- Token數
- 滲濾型
- join datatype
- Meta-Fields
- _all field
- _field_names field
- _id field
- _index field
- _meta field
- _routing field
- _source field
- _type field
- _uid field
- Mapping parameters
- analyzer(分析器)
- normalizer(歸一化)
- boost(提升)
- Coerce(強制類型轉換)
- copy_to(合并參數)
- doc_values(文檔值)
- dynamic(動態設置)
- enabled(開啟字段)
- eager_global_ordinals
- fielddata(字段數據)
- format (日期格式)
- ignore_above(忽略超越限制的字段)
- ignore_malformed(忽略格式不對的數據)
- index (索引)
- index_options(索引設置)
- fields(字段)
- Norms (標準信息)
- null_value(空值)
- position_increment_gap(短語位置間隙)
- properties (屬性)
- search_analyzer (搜索分析器)
- similarity (匹配方法)
- store(存儲)
- Term_vectors(詞根信息)
- Dynamic Mapping
- Dynamic field mapping(動態字段映射)
- Dynamic templates(動態模板)
- default mapping(mapping中的_default_)
- Analysis
- Anatomy of an analyzer(分析器的分析)
- Testing analyzers(測試分析器)
- Analyzers(分析器)
- Configuring built-in analyzers(配置內置分析器)
- Standard Analyzer(標準分析器)
- Simple Analyzer(簡單分析器)
- 空白分析器
- Stop Analyzer
- Keyword Analyzer
- 模式分析器
- 語言分析器
- 指紋分析器
- 自定義分析器
- Normalizers
- Tokenizers(分詞器)
- Standard Tokenizer(標準分詞器)
- Letter Tokenizer
- Lowercase Tokenizer (小寫分詞器)
- Whitespace Analyzer
- UAX URL Email Tokenizer
- Classic Tokenizer
- Thai Tokenizer(泰語分詞器)
- NGram Tokenizer
- Edge NGram Tokenizer
- Keyword Analyzer
- Pattern Tokenizer
- Simple Pattern Tokenizer
- Simple Pattern Split Tokenizer
- Path Hierarchy Tokenizer(路徑層次分詞器)
- Token Filters(詞元過濾器)
- Standard Token Filter
- ASCII Folding Token Filter
- Flatten Graph Token Filter
- Length Token Filter
- Lowercase Token Filter
- Uppercase Token Filter
- NGram Token Filter
- Edge NGram Token Filter
- Porter Stem Token Filter
- Shingle Token Filter
- Stop Token Filter
- Word Delimiter Token Filter
- Word Delimiter Graph Token Filter
- Stemmer Token Filter
- Stemmer Override Token Filter
- Keyword Marker Token Filter
- Keyword Repeat Token Filter
- KStem Token Filter
- Snowball Token Filter
- Phonetic Token Filter
- Synonym Token Filter
- Synonym Graph Token Filter
- Compound Word Token Filters
- Reverse Token Filter
- Elision Token Filter
- Truncate Token Filter
- Unique Token Filter
- Pattern Capture Token Filter
- Pattern Replace Token Filter
- Trim Token Filter
- Limit Token Count Token Filter
- Hunspell Token Filter
- Common Grams Token Filter
- Normalization Token Filter
- CJK Width Token Filter
- CJK Bigram Token Filter
- Delimited Payload Token Filter
- Keep Words Token Filter
- Keep Types Token Filter
- Classic Token Filter
- Apostrophe Token Filter
- Decimal Digit Token Filter
- Fingerprint Token Filter
- Minhash Token Filter
- Character Filters(字符過濾器)
- HTML Strip Character Filter
- Mapping Character Filter
- Pattern Replace Character Filter
- 模塊
- Cluster
- 集群級路由和碎片分配
- 基于磁盤的分片分配
- 分片分配awareness
- 分片分配過濾
- Miscellaneous cluster settings
- Scripting
- Painless Scripting Language
- Lucene Expressions Language
- Advanced scripts using script engines
- Snapshot And Restore
- Thread Pool
- Index Modules(索引模塊)
- 預處理節點
- Pipeline Definition
- Ingest APIs
- Put Pipeline API
- Get Pipeline API
- Delete Pipeline API
- Simulate Pipeline API
- Accessing Data in Pipelines
- Handling Failures in Pipelines
- Processors
- Monitoring Elasticsearch
- X-Pack APIs
- X-Pack Commands
- How To
- Testing(測試)
- Glossary of terms
- Release Notes
- X-Pack Release Notes