Elasticsearch Query DSL備忘（1）（Constant score query和Bool Query）
阿新 • • 發佈：2018-12-30
Query DSL (Domain Specific Language)，基於json的查詢方式
1、Constant score query，常量分值查詢，目的就是返回指定的score，一般都結合filter使用，因為filter context忽略score。
GET /customer/_search
{
"query": {
"constant_score": {
"filter": {
"match": {
"addr": "天津，北京"
}
},
"boost": 5.2
}
}
}
result:返回結果中score都是被指定的5.2
{
"took" : 8,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : 2,
"max_score" : 5.2,
"hits" : [
{
"_index" : "customer",
"_type" : "doc",
"_id" : "510221197801023611",
"_score" : 5.2, 2、bool query，布林查詢
Bool查詢對應Lucene中的BooleanQuery，它由一個或者多個子句組成，每個子句都有特定的型別。
- must 返回的文件必須滿足must子句的條件，並且參與計算分值
- filter 返回的文件必須滿足filter子句的條件。但是不會像must一樣參與計算分值
- should 返回的文件可能滿足should子句的條件。bool查詢在query context中，並且有一個must或filter子句，即使沒有一個should查詢匹配，文件也會進行bool匹配。在這種情況下，這些should僅用於影響分數。如果在filter context中，或者沒有must或filter子句，那麼should子句必須和文件匹配，才能匹配bool查詢。這種行為由minimum_should_match 參與決定。
- must_not 返回的文件必須不滿足must_not定義的條件。
官網的例子：
POST _search
{
"query": {
"bool" : {
"must" : {
"term" : { "user" : "kimchy" }
},
"filter": {
"term" : { "tag" : "tech" }
},
"must_not" : {
"range" : {
"age" : { "gte" : 10, "lte" : 20 }
}
},
"should" : [
{ "term" : { "tag" : "wow" } },
{ "term" : { "tag" : "elasticsearch" } }
],
"minimum_should_match" : 1,
"boost" : 1.0
}
}
}
bool查詢案例分解：
第一步：查詢name為“李雲龍”的文件
GET /customer/_search
{
"query": {
"bool": {
"must": {
"term":{"name.keyword":"李雲龍"}
}
}
}
}
返回三個文件：
{
"took" : 0,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : 3,
"max_score" : 1.4916549,
"hits" : [
{
"_index" : "customer",
"_type" : "doc",
"_id" : "4",
"_score" : 1.4916549,
"_source" : {
"name" : "李雲龍",
"id" : "510221197001013611",
"addr" : "昆明市滇池路陽光時代1棟1單元",
"tel" : "13808712808"
}
},
{
"_index" : "customer",
"_type" : "doc",
"_id" : "224",
"_score" : 1.4916549,
"_source" : {
"name" : "李雲龍",
"id" : "224",
"addr" : "天津市陽光路2008號",
"tel" : "13908712808"
}
},
{
"_index" : "customer",
"_type" : "doc",
"_id" : "510221197001013611",
"_score" : 1.4916549,
"_source" : {
"name" : "李雲龍",
"id" : "510221197001013611",
"addr" : "上海市浦東區華北路8號",
"tel" : "13908712808"
}
}
]
}
}
第二步：加入過濾條件，只保留id為510221197001013611的文件
GET /customer/_search
{
"query": {
"bool": {
"must": {
"term":{"name.keyword":"李雲龍"}
},
"filter": {
"term": {
"id": "510221197001013611"
}
}
}
}
}
返回結果減少到2個文件，並且score相同：
{
"took" : 0,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : 2,
"max_score" : 1.4916549,
"hits" : [
{
"_index" : "customer",
"_type" : "doc",
"_id" : "4",
"_score" : 1.4916549,
"_source" : {
"name" : "李雲龍",
"id" : "510221197001013611",
"addr" : "昆明市滇池路陽光時代1棟1單元",
"tel" : "13808712808"
}
},
{
"_index" : "customer",
"_type" : "doc",
"_id" : "510221197001013611",
"_score" : 1.4916549,
"_source" : {
"name" : "李雲龍",
"id" : "510221197001013611",
"addr" : "上海市浦東區華北路8號",
"tel" : "13908712808"
}
}
]
}
}
第三步：使用should，判斷addr中必須有昆明市，這種情況下should子句會影響計分
GET /customer/_search
{
"query": {
"bool": {
"must": {
"term":{"name.keyword":"李雲龍"}
},
"filter": {
"term": {
"id": "510221197001013611"
}
},
"should": [
{"match": {
"addr": "昆明市"
}}
]
}
}
}
返回結果中，地址是昆明市的文件score加重
{
"took" : 1,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : 2,
"max_score" : 3.408528,
"hits" : [
{
"_index" : "customer",
"_type" : "doc",
"_id" : "4",
"_score" : 3.408528,
"_source" : {
"name" : "李雲龍",
"id" : "510221197001013611",
"addr" : "昆明市滇池路陽光時代1棟1單元",
"tel" : "13808712808"
}
},
{
"_index" : "customer",
"_type" : "doc",
"_id" : "510221197001013611",
"_score" : 1.5720221,
"_source" : {
"name" : "李雲龍",
"id" : "510221197001013611",
"addr" : "上海市浦東區華北路8號",
"tel" : "13908712808"
}
}
]
}
}
第四步：加入must_not排除上海
GET /customer/_search
{
"query": {
"bool": {
"must": {
"term":{"name.keyword":"李雲龍"}
},
"filter": {
"term": {
"id": "510221197001013611"
}
},
"should": [
{"match": {
"addr": "昆明市"
}}
],
"must_not": [
{"match": {
"addr": "上海"
}}
]
}
}
}
只返回一個文件：
{
"took" : 2,
"timed_out" : false,
"_shards" : {
"total" : 1,
"successful" : 1,
"skipped" : 0,
"failed" : 0
},
"hits" : {
"total" : 1,
"max_score" : 3.408528,
"hits" : [
{
"_index" : "customer",
"_type" : "doc",
"_id" : "4",
"_score" : 3.408528,
"_source" : {
"name" : "李雲龍",
"id" : "510221197001013611",
"addr" : "昆明市滇池路陽光時代1棟1單元",
"tel" : "13808712808"
}
}
]
}
}