聚合分析對(duì)應(yīng)數(shù)據(jù)庫(kù)中的聚合函數(shù)。在 Elasticsearch 中使用 aggs 標(biāo)簽表示。
計(jì)算所有商品的價(jià)格總和
GET /store/product/_search
{
"aggs": {
"sum_price": {
"sum": {
"field": "price"
}
}
}
}
返回結(jié)果：
{
"took": 50,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 1,
"hits": [
{
"_index": "store",
"_type": "product",
"_id": "2",
"_score": 1,
"_source": {
"name": "jiajieshi yagao",
"desc": "youxiao fangzhu",
"price": 25,
"producer": "jiajieshi producer",
"tags": [
"fangzhu"
]
}
},
{
"_index": "store",
"_type": "product",
"_id": "4",
"_score": 1,
"_source": {
"name": "special yagao",
"desc": "special meibai",
"price": 50,
"producer": "special yagao producer",
"tags": [
"meibai"
]
}
},
{
"_index": "store",
"_type": "product",
"_id": "1",
"_score": 1,
"_source": {
"name": "gaolujie yagao",
"desc": "gaoxiao meibai",
"price": 30,
"producer": "gaolujie producer",
"tags": [
"meibai",
"fangzhu"
]
}
},
{
"_index": "store",
"_type": "product",
"_id": "3",
"_score": 1,
"_source": {
"name": "zhonghua yagao",
"desc": "caoben zhiwu",
"price": 40,
"producer": "zhonghua producer",
"tags": [
"qingxin"
]
}
}
]
},
"aggregations": {
"sum_price": {
"value": 145
}
}
}
在返回結(jié)果中如果不想輸出所有商品的記錄，可以使用 size：0 進(jìn)行控制：
GET /store/product/_search
{
"size": 0,
"aggs": {
"sum_price": {
"sum": {
"field": "price"
}
}
}
}
返回結(jié)果：
{
"took": 6,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 0,
"hits": []
},
"aggregations": {
"sum_price": {
"value": 145
}
}
}
搜索最貴的商品
GET /store/product/_search
{
"size": 0,
"aggs": {
"max_price": {
"max": {
"field": "price"
}
}
}
}
返回結(jié)果：
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 0,
"hits": []
},
"aggregations": {
"max_price": {
"value": 50
}
}
}
計(jì)算所有商品的平均價(jià)格
GET /store/product/_search
{
"size": 0,
"aggs": {
"avg_price": {
"avg": {
"field": "price"
}
}
}
}
返回結(jié)果：
{
"took": 7,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 0,
"hits": []
},
"aggregations": {
"avg_price": {
"value": 36.25
}
}
}
統(tǒng)計(jì)每個(gè)標(biāo)簽下的商品數(shù)量
GET /store/product/_search
{
"size": 0,
"aggs": {
"group_by_tags": {
"terms": {
"field": "tags"
}
}
}
}
如果上來(lái)直接這么操作會(huì)報(bào)錯(cuò)：
{
"error": {
"root_cause": [
{
"type": "illegal_argument_exception",
"reason": "Fielddata is disabled on text fields by default. Set fielddata=true on [tags] 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": "store",
"node": "-DEY-JneQYmg3g1leawBvA",
"reason": {
"type": "illegal_argument_exception",
"reason": "Fielddata is disabled on text fields by default. Set fielddata=true on [tags] 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
}
需要先將 text field 的 fielddata 屬性設(shè)置為 true：
PUT /store/_mapping/product
{
"properties": {
"tags": {
"type": "text",
"fielddata": true
}
}
}
接著再去執(zhí)行上面的命令，順利返回結(jié)果：
{
"took": 408,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 0,
"hits": []
},
"aggregations": {
"group_by_tags": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "fangzhu",
"doc_count": 2
},
{
"key": "meibai",
"doc_count": 2
},
{
"key": "qingxin",
"doc_count": 1
}
]
}
}
}
對(duì)名稱中包含 "yagao" 的商品，統(tǒng)計(jì)每個(gè)標(biāo)簽下的商品數(shù)量
GET /store/product/_search
{
"size": 0,
"query": {
"match": {
"name": "yagao"
}
},
"aggs": {
"group_by_tags": {
"terms": {
"field": "tags"
}
}
}
}
返回結(jié)果：
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 0,
"hits": []
},
"aggregations": {
"group_by_tags": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "fangzhu",
"doc_count": 2
},
{
"key": "meibai",
"doc_count": 2
},
{
"key": "qingxin",
"doc_count": 1
}
]
}
}
}
先按照標(biāo)簽進(jìn)行分組，再計(jì)算每組商品的平均價(jià)格
GET /store/product/_search
{
"size": 0,
"aggs": {
"group_by_tags": {
"terms": {
"field": "tags"
},
"aggs": {
"avg_price": {
"avg": {
"field": "price"
}
}
}
}
}
}
返回結(jié)果：
{
"took": 4,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 0,
"hits": []
},
"aggregations": {
"group_by_tags": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "fangzhu",
"doc_count": 2,
"avg_price": {
"value": 27.5
}
},
{
"key": "meibai",
"doc_count": 2,
"avg_price": {
"value": 40
}
},
{
"key": "qingxin",
"doc_count": 1,
"avg_price": {
"value": 40
}
}
]
}
}
}
先按照標(biāo)簽進(jìn)行分組，再計(jì)算每組商品的平均價(jià)格，并按照價(jià)格倒序排序
GET /store/product/_search
{
"size": 0,
"aggs": {
"group_by_tags": {
"terms": {
"field": "tags",
"order": {
"avg_price": "desc"
}
},
"aggs": {
"avg_price": {
"avg": {
"field": "price"
}
}
}
}
}
}
返回結(jié)果：
{
"took": 5,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 0,
"hits": []
},
"aggregations": {
"group_by_tags": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "meibai",
"doc_count": 2,
"avg_price": {
"value": 40
}
},
{
"key": "qingxin",
"doc_count": 1,
"avg_price": {
"value": 40
}
},
{
"key": "fangzhu",
"doc_count": 2,
"avg_price": {
"value": 27.5
}
}
]
}
}
}
先按照指定的價(jià)格區(qū)間進(jìn)行分組，然后在每組內(nèi)按照標(biāo)簽進(jìn)行分組，最后再計(jì)算每組的平均價(jià)格
{
"size": 0,
"aggs": {
"range_by_price": {
"range": {
"field": "price",
"ranges": [
{
"from": 0,
"to": 20
},
{
"from": 20,
"to": 40
},
{
"from": 40,
"to": 60
}
]
},
"aggs": {
"group_by_tags": {
"terms": {
"field": "tags"
},
"aggs": {
"avg_price": {
"avg": {
"field": "price"
}
}
}
}
}
}
}
}
返回結(jié)果：
{
"took": 2,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 0,
"hits": []
},
"aggregations": {
"range_by_price": {
"buckets": [
{
"key": "0.0-20.0",
"from": 0,
"to": 20,
"doc_count": 0,
"group_by_tags": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": []
}
},
{
"key": "20.0-40.0",
"from": 20,
"to": 40,
"doc_count": 2,
"group_by_tags": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "fangzhu",
"doc_count": 2,
"avg_price": {
"value": 27.5
}
},
{
"key": "meibai",
"doc_count": 1,
"avg_price": {
"value": 30
}
}
]
}
},
{
"key": "40.0-60.0",
"from": 40,
"to": 60,
"doc_count": 2,
"group_by_tags": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "meibai",
"doc_count": 1,
"avg_price": {
"value": 50
}
},
{
"key": "qingxin",
"doc_count": 1,
"avg_price": {
"value": 40
}
}
]
}
}
]
}
}
}
從結(jié)果中可以看出
{
"from": 20,
"to": 40
}
包含前面不包含后面，即：[20, 40)。
