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今天松哥和大家分享一个 Es 中的简单话题--管道聚合。
以下是视频笔记：
注意，笔记只是视频内容的一个简要记录，因此笔记内容比较简单，完整的内容可以查看视频。
24.ElasticSearch 管道聚合
管道聚合相当于在之前聚合的基础上，再次聚合。
24.1 Avg Bucket Aggregation
计算聚合平均值。例如，统计每个出版社所出版图书的平均值，然后再统计所有出版社的平均值：
代码语言：javascript复制GET books/_search
{
"aggs": {
"book_count": {
"terms": {
"field": "publish",
"size": 3
},
"aggs": {
"book_avg": {
"avg": {
"field": "price"
}
}
}
},
"avg_book":{
"avg_bucket": {
"buckets_path": "book_count>book_avg"
}
}
}
}
24.2 Max Bucket Aggregation
统计每个出版社所出版图书的平均值，然后再统计平均值中的最大值：
代码语言：javascript复制GET books/_search
{
"aggs": {
"book_count": {
"terms": {
"field": "publish",
"size": 3
},
"aggs": {
"book_avg": {
"avg": {
"field": "price"
}
}
}
},
"avg_book":{
"max_bucket": {
"buckets_path": "book_count>book_avg"
}
}
}
}
24.3 Min Bucket Aggregation
统计每个出版社所出版图书的平均值，然后再统计平均值中的最小值：
代码语言：javascript复制GET books/_search
{
"aggs": {
"book_count": {
"terms": {
"field": "publish",
"size": 3
},
"aggs": {
"book_avg": {
"avg": {
"field": "price"
}
}
}
},
"avg_book":{
"min_bucket": {
"buckets_path": "book_count>book_avg"
}
}
}
}
24.4 Sum Bucket Aggregation
统计每个出版社所出版图书的平均值，然后再统计平均值之和：
代码语言：javascript复制GET books/_search
{
"aggs": {
"book_count": {
"terms": {
"field": "publish",
"size": 3
},
"aggs": {
"book_avg": {
"avg": {
"field": "price"
}
}
}
},
"avg_book":{
"sum_bucket": {
"buckets_path": "book_count>book_avg"
}
}
}
}
24.5 Stats Bucket Aggregation
统计每个出版社所出版图书的平均值，然后再统计平均值的各种数据：
代码语言：javascript复制GET books/_search
{
"aggs": {
"book_count": {
"terms": {
"field": "publish",
"size": 3
},
"aggs": {
"book_avg": {
"avg": {
"field": "price"
}
}
}
},
"avg_book":{
"stats_bucket": {
"buckets_path": "book_count>book_avg"
}
}
}
}
24.6 Extended Stats Bucket Aggregation
代码语言：javascript复制GET books/_search
{
"aggs": {
"book_count": {
"terms": {
"field": "publish",
"size": 3
},
"aggs": {
"book_avg": {
"avg": {
"field": "price"
}
}
}
},
"avg_book":{
"extended_stats_bucket": {
"buckets_path": "book_count>book_avg"
}
}
}
}
24.7 Percentiles Bucket Aggregation
代码语言：javascript复制GET books/_search
{
"aggs": {
"book_count": {
"terms": {
"field": "publish",
"size": 3
},
"aggs": {
"book_avg": {
"avg": {
"field": "price"
}
}
}
},
"avg_book":{
"percentiles_bucket": {
"buckets_path": "book_count>book_avg"
}
}
}
}
