bucket:
数据分组，一些数据按照某个字段进行bucket划分，这个字段值相同的数据放到一个bucket中。类似于Mysql中的group by后的查询结果。
metric：
对一个数据分组执行的统计，比如计算最大值，最小值，平均值等
类似于Mysql中的max(),min(),avg()函数的值，都是在group by后使用的。
数据准备
PUT /music { "mappings": { "properties": { "id": { "type": "keyword" }, "author": { "type": "text", "analyzer": "english", "fields": { "keyword": { "type": "keyword", "ignore_above": 256 } } }, "name": { "type": "text", "fields": { "keyword": { "type": "keyword", "ignore_above": 256 } } }, "content": { "type": "text", "fields": { "keyword": { "type": "keyword", "ignore_above": 256 } } }, "language": { "type": "text", "analyzer": "english", "fielddata": true }, "tags": { "type": "text", "analyzer": "english" }, "length": { "type": "long" }, "likes": { "type": "long" }, "isRelease": { "type": "boolean" }, "releaseDate": { "type": "date" } } } }
POST /music/_doc/_bulk { "index": {}} { "author" : "zhangsan", "name" : "red", "content" : "honda", "language":"ch","tags":"tags","length":3,"likes":10,"isRelease":true,"releaseDate" : "2021-10-28" } { "index": {}} { "author" : "lisi", "name" : "blue", "content" : "honda", "language":"en","tags":"tags","length":3,"likes":100,"isRelease":true,"releaseDate" : "2021-10-28" } { "index": {}} { "author" : "zhangsan1", "name" : "red", "content" : "honda", "language":"ch","tags":"tags","length":30,"likes":10,"isRelease":true,"releaseDate" : "2021-11-28" } { "index": {}} { "author" : "lisi1", "name" : "blue", "content" : "honda", "language":"en","tags":"tags","length":30,"likes":100,"isRelease":true,"releaseDate" : "2021-11-28" } { "index": {}} { "author" : "zhangsan2", "name" : "red", "content" : "honda", "language":"ch","tags":"tags","length":80,"likes":10,"isRelease":true,"releaseDate" : "2021-11-28" } { "index": {}} { "author" : "lisi2", "name" : "blue", "content" : "honda", "language":"en","tags":"tags","length":80,"likes":100,"isRelease":true,"releaseDate" : "2022-10-28" } { "index": {}} { "author" : "zhangsan2", "name" : "red", "content" : "honda", "language":"ch","tags":"tags","length":80,"likes":10,"isRelease":true,"releaseDate" : "2022-10-28" } { "index": {}} { "author" : "lisi2", "name" : "blue", "content" : "honda", "language":"en","tags":"tags","length":80,"likes":100,"isRelease":true,"releaseDate" : "2022-10-28" }
1、统计目前收录的每种语言的歌曲数量
GET /music/_doc/_search { "size": 0, "aggs": { "song_qty_by_language": { "terms": { "field": "language" } } } } //返回结果 #! Deprecation: [types removal] Specifying types in search requests is deprecated. { "took" : 25, "timed_out" : false, "_shards" : { "total" : 1, "successful" : 1, "skipped" : 0, "failed" : 0 }, "hits" : { "total" : { "value" : 8, "relation" : "eq" }, "max_score" : null, "hits" : [ ] }, "aggregations" : { "song_qty_by_language" : { "doc_count_error_upper_bound" : 0, "sum_other_doc_count" : 0, "buckets" : [ { "key" : "ch", "doc_count" : 4 }, { "key" : "en", "doc_count" : 4 } ] } } }
size:0 表示只要统计后的结果，原始数据不展现,如果是大于0的，则会返回原数据
aggs：固定语法 ，聚合分析都要声明aggs
song_qty_by_language：聚合的名称，可以随便写，建议规范命名
terms：按什么字段进行分组
field：具体的字段名称
2、按语种统计每种语种歌曲的平均时长
GET /music/_doc/_search { "size": 0, "aggs": { "lang": { "terms": { "field": "language" }, "aggs": { "length_avg": { "avg": { "field": "length" } } } } } } //返回 { "took" : 1, "timed_out" : false, "_shards" : { "total" : 1, "successful" : 1, "skipped" : 0, "failed" : 0 }, "hits" : { "total" : { "value" : 8, "relation" : "eq" }, "max_score" : null, "hits" : [ ] }, "aggregations" : { "lang" : { "doc_count_error_upper_bound" : 0, "sum_other_doc_count" : 0, "buckets" : [ { "key" : "ch", "doc_count" : 4, "length_avg" : { "value" : 48.25 } }, { "key" : "en", "doc_count" : 4, "length_avg" : { "value" : 48.25 } } ] } } }
两层aggs聚合查询，先按语种统计，得到数据分组，再在数据分组里算平均时长。
3、统计最长时长、最短时长等的歌曲
GET /music/_doc/_search { "size": 0, "aggs": { "color": { "terms": { "field": "language" }, "aggs": { "length_avg": { "avg": { "field": "length" } }, "length_max": { "max": { "field": "length" } }, "length_min": { "min": { "field": "length" } }, "length_sum": { "sum": { "field": "length" } } } } } } //返回 #! Deprecation: [types removal] Specifying types in search requests is deprecated. { "took" : 59, "timed_out" : false, "_shards" : { "total" : 1, "successful" : 1, "skipped" : 0, "failed" : 0 }, "hits" : { "total" : { "value" : 8, "relation" : "eq" }, "max_score" : null, "hits" : [ ] }, "aggregations" : { "color" : { "doc_count_error_upper_bound" : 0, "sum_other_doc_count" : 0, "buckets" : [ { "key" : "ch", "doc_count" : 4, "length_sum" : { "value" : 193.0 }, "length_max" : { "value" : 80.0 }, "length_min" : { "value" : 3.0 }, "length_avg" : { "value" : 48.25 } }, { "key" : "en", "doc_count" : 4, "length_sum" : { "value" : 193.0 }, "length_max" : { "value" : 80.0 }, "length_min" : { "value" : 3.0 }, "length_avg" : { "value" : 48.25 } } ] } } }
4、按时长分段统计歌曲平均时长
以30秒为一段，看各段区间的平均值。
histogram语法位置跟terms一样，作范围分区，搭配interval参数一起使用
interval:30表示分的区间段为[0,30),[30,60),[60,90),[90,120)
段的闭合关系是左开右闭，如果数据在某段区间内没有，也会返回空的区间。
GET /music/_doc/_search { "size": 0, "aggs": { "sales_price_range": { "histogram": { "field": "length", "interval": 30 }, "aggs": { "length_avg": { "avg": { "field": "length" } } } } } }
5、按上架日期分段统计新歌数量
GET /music/_doc/_search { "size": 0, "aggs": { "sales": { "date_histogram": { "field": "releaseDate", "interval": "month", "format": "yyyy-MM-dd", "min_doc_count": 0, "extended_bounds": { "min": "2000-10-01", "max": "2088-12-31" } } } } }
6、统计今年每个季度新发布歌曲的点赞数量,以及每个语种的点赞数量
GET /music/_doc/_search { "size": 0, "aggs": { "sales": { "date_histogram": { "field": "releaseDate", "interval": "quarter", "format": "yyyy-MM-dd", "min_doc_count": 0, "extended_bounds": { "min": "2022-01-01", "max": "2022-08-31" } }, "aggs": { "lang_qty": { "terms": { "field": "language" }, "aggs": { "like_sum": { "sum": { "field": "likes" } } } }, "total" :{ "sum": { "field": "likes" } } } } } }
7、查询某种语种的歌曲数量
相当于mysql中where与group by联合使用
GET /music/_doc/_search { "size": 0, "query": { "match": { "language": "en" } }, "aggs": { "sales": { "terms": { "field": "language" } } } }
8、指定作者的歌与全部歌曲的点赞数量对比
GET /music/_doc/_search { "size": 0, "query": { "match": { "author": "zhangsan" } }, "aggs": { "likes": { "sum": { "field": "likes" } }, "all": { "global": {}, "aggs": { "all_likes": { "sum": { "field": "likes" } } } } } }
9、统计近2月，近1月的点赞数
GET /music/_doc/_search { "size": 0, "aggs": { "recent_60d": { "filter": { "range": { "releaseDate": { "gte": "now-60d" } } }, "aggs": { "recent_60d_likes_sum": { "sum": { "field": "likes" } } } }, "recent_30d": { "filter": { "range": { "releaseDate": { "gte": "now-30d" } } }, "aggs": { "recent_30d_likes_sum": { "avg": { "field": "likes" } } } } } }
10、统计排序
默认按doc_count降序排序，排序规则可以改，order里面可以指定aggs的别名，如length_avg，类似于mysql的order by cnt asc。
计算每种语言的歌曲数量，和每种语言的歌曲平均时长
GET /music/_doc/_search { "size": 0, "aggs": { "group_by_lang": { "terms": { "field": "language", "order": { "length_avg": "desc" } }, "aggs": { "length_avg": { "avg": { "field": "length" } } } } } }
bucket:
2
数据分组，一些数据按照某个字段进行bucket划分，这个字段值相同的数据放到一个bucket中。类似于Mysql中的group by后的查询结果。
3
4
metric：
5
对一个数据分组执行的统计，比如计算最大值，最小值，平均值等
6
类似于Mysql中的max(),min(),avg()函数的值，都是在group by后使用的。