在Elasticsearch中，通過使用基於JSON的查詢進行搜尋。 查詢由兩個子句組成 -
Elasticsearch支援大量查詢。 查詢從查詢關鍵字開始，然後以JSON物件的形式在其中包含條件和過濾器。以下描述了不同型別的查詢 -
這是最基本的查詢; 它返回所有內容，並為每個物件的分數為1.0。 例如，
POST http://localhost:9200/schools*/_search
請求正文
{
"query":{
"match_all":{}
}
}
響應
{
"took":1, "timed_out":false, "_shards":{"total":10, "successful":10, "failed":0},
"hits":{
"total":5, "max_score":1.0, "hits":[
{
"_index":"schools", "_type":"school", "_id":"2", "_score":1.0,
"_source":{
"name":"Saint Paul School", "description":"ICSE Affiliation",
"street":"Dawarka", "city":"Delhi", "state":"Delhi",
"zip":"110075", "location":[28.5733056, 77.0122136], "fees":5000,
"tags":["Good Faculty", "Great Sports"], "rating":"4.5"
}
},
{
"_index":"schools_gov", "_type":"school", "_id":"2", "_score":1.0,
"_source":{
"name":"Government School", "description":"State Board Affiliation",
"street":"Hinjewadi", "city":"Pune", "state":"MH", "zip":"411057",
"location":[18.599752, 73.6821995], "fees":500, "tags":["Great Sports"],
"rating":"4"
}
},
{
"_index":"schools", "_type":"school", "_id":"1", "_score":1.0,
"_source":{
"name":"Central School", "description":"CBSE Affiliation",
"street":"Nagan", "city":"paprola", "state":"HP",
"zip":"176115", "location":[31.8955385, 76.8380405],
"fees":2200, "tags":["Senior Secondary", "beautiful campus"],
"rating":"3.3"
}
},
{
"_index":"schools_gov", "_type":"school", "_id":"1", "_score":1.0,
"_source":{
"name":"Model School", "description":"CBSE Affiliation",
"street":"silk city", "city":"Hyderabad", "state":"AP",
"zip":"500030", "location":[17.3903703, 78.4752129], "fees":700,
"tags":["Senior Secondary", "beautiful campus"], "rating":"3"
}
},
{
"_index":"schools", "_type":"school", "_id":"3", "_score":1.0,
"_source":{
"name":"Crescent School", "description":"State Board Affiliation",
"street":"Tonk Road", "city":"Jaipur", "state":"RJ", "zip":"176114",
"location":[26.8535922, 75.7923988], "fees":2500,
"tags":["Well equipped labs"], "rating":"4.5"
}
}
]
}
}
這些查詢用於搜尋整個文字，如章節或新聞文章。 此查詢根據與特定索引或文件相關聯的分析器一起工作。 在本節中，我們將討論不同型別的全文查詢。
此查詢將文字或短語與一個或多個欄位的值匹配。 例如，
POST http://localhost:9200/schools*/_search
請求正文
{
"query":{
"match" : {
"city":"pune"
}
}
}
響應
{
"took":1, "timed_out":false, "_shards":{"total":10, "successful":10, "failed":0},
"hits":{
"total":1, "max_score":0.30685282, "hits":[{
"_index":"schools_gov", "_type":"school", "_id":"2", "_score":0.30685282,
"_source":{
"name":"Government School", "description":"State Board Afiliation",
"street":"Hinjewadi", "city":"Pune", "state":"MH", "zip":"411057",
"location":[18.599752, 73.6821995], "fees":500,
"tags":["Great Sports"], "rating":"4"
}
}]
}
}
此查詢將文字或短語與多個欄位匹配。 例如，
POST http://localhost:9200/schools*/_search
請求正文
{
"query":{
"multi_match" : {
"query": "hyderabad",
"fields": [ "city", "state" ]
}
}
}
響應
{
"took":16, "timed_out":false, "_shards":{"total":10, "successful":10, "failed":0},
"hits":{
"total":1, "max_score":0.09415865, "hits":[{
"_index":"schools_gov", "_type":"school", "_id":"1", "_score":0.09415865,
"_source":{
"name":"Model School", " description":"CBSE Affiliation",
"street":"silk city", "city":"Hyderabad", "state":"AP",
"zip":"500030", "location":[17.3903703, 78.4752129], "fees":700,
"tags":["Senior Secondary", "beautiful campus"], "rating":"3"
}
}]
}
}
此查詢使用查詢解析器和query_string關鍵字。 例如，
POST http://localhost:9200/schools/_search
請求正文
{
"query":{
"query_string":{
"query":"good faculty"
}
}
}
響應
{
"took":16, "timed_out":false, "_shards":{"total":10, "successful":10, "failed":0},
"hits":{
"total":1, "max_score":0.09492774, "hits":[{
"_index":"schools", "_type":"school", "_id":"2", "_score":0.09492774,
"_source":{
"name":"Saint Paul School", "description":"ICSE Affiliation",
"street":"Dawarka", "city":"Delhi", "state":"Delhi",
"zip":"110075", "location":[28.5733056, 77.0122136],
"fees":5000, "tags":["Good Faculty", "Great Sports"],
"rating":"4.5"
}
}]
}
}
這些查詢主要處理結構化資料，如數位，日期和列舉。 例如，
POST http://localhost:9200/schools/_search
請求正文
{
"query":{
"term":{"zip":"176115"}
}
}
響應
{
"took":1, "timed_out":false, "_shards":{"total":10, "successful":10, "failed":0},
"hits":{
"total":1, "max_score":0.30685282, "hits":[{
"_index":"schools", "_type":"school", "_id":"1", "_score":0.30685282,
"_source":{
"name":"Central School", "description":"CBSE Affiliation",
"street":"Nagan", "city":"paprola", "state":"HP", "zip":"176115",
"location":[31.8955385, 76.8380405], "fees":2200,
"tags":["Senior Secondary", "beautiful campus"], "rating":"3.3"
}
}]
}
}
此查詢用於查詢值的範圍之間的值的物件。 為此，需要使用類似 -
例如 -
POST http://localhost:9200/schools*/_search
請求正文
{
"query":{
"range":{
"rating":{
"gte":3.5
}
}
}
}
響應
{
"took":31, "timed_out":false, "_shards":{"total":10, "successful":10, "failed":0},
"hits":{
"total":3, "max_score":1.0, "hits":[
{
"_index":"schools", "_type":"school", "_id":"2", "_score":1.0,
"_source":{
"name":"Saint Paul School", "description":"ICSE Affiliation",
"street":"Dawarka", "city":"Delhi", "state":"Delhi",
"zip":"110075", "location":[28.5733056, 77.0122136], "fees":5000,
"tags":["Good Faculty", "Great Sports"], "rating":"4.5"
}
},
{
"_index":"schools_gov", "_type":"school", "_id":"2", "_score":1.0,
"_source":{
"name":"Government School", "description":"State Board Affiliation",
"street":"Hinjewadi", "city":"Pune", "state":"MH", "zip":"411057",
"location":[18.599752, 73.6821995] "fees":500,
"tags":["Great Sports"], "rating":"4"
}
},
{
"_index":"schools", "_type":"school", "_id":"3", "_score":1.0,
"_source":{
"name":"Crescent School", "description":"State Board Affiliation",
"street":"Tonk Road", "city":"Jaipur", "state":"RJ", "zip":"176114",
"location":[26.8535922, 75.7923988], "fees":2500,
"tags":["Well equipped labs"], "rating":"4.5"
}
}
]
}
}
其他型別的期限級查詢是 -
型別查詢 - 具有特定型別的文件。 例如，
POST http://localhost:9200/schools*/_search
請求正文
{
"query":{
"type" : {
"value" : "school"
}
}
}
響應
存在於指定的索引中的所有學校的JSON物件。
這些查詢是通過使用如和，或，非和或等，用於不同索引或具有函式呼叫等的布林運算子彼此合併的不同查詢的集合。例如，
POST http://localhost:9200/schools*/_search
請求正文
{
"query":{
"filtered":{
"query":{
"match":{
"state":"UP"
}
},
"filter":{
"range":{
"rating":{
"gte":4.0
}
}
}
}
}
}
響應
{
"took":16, "timed_out":false, "_shards":{"total":10, "successful":10, "failed":0},
"hits":{"total":0, "max_score":null, "hits":[]}
}
這些查詢用於包含多個對映或文件的位置。 連線查詢有兩種型別 -
巢狀查詢
這些查詢處理巢狀對映(將在下一章閱讀了解更多內容)。
has_child和has_parent查詢
這些查詢用於檢索在查詢中匹配的文件的子文件或父文件。 例如，
POST http://localhost:9200/tutorials/_search
請求正文
{
"query":
{
"has_child" : {
"type" : "article", "query" : {
"match" : {
"Text" : "This is article 1 of chapter 1"
}
}
}
}
}
響應
{
"took":21, "timed_out":false, "_shards":{"total":5, "successful":5, "failed":0},
"hits":{
"total":1, "max_score":1.0, "hits":[{
"_index":"tutorials", "_type":"chapter", "_id":"1", "_score":1.0,
"_source":{
"Text":"this is chapter one"
}
}]
}
}
這些查詢處理地理位置和地理點。這些查詢有助於查詢任何位置附近的學校或任何其他地理物件。需要使用地理位置資料型別。 例如，
POST http://localhost:9200/schools*/_search
請求正文
{
"query":{
"filtered":{
"filter":{
"geo_distance":{
"distance":"100km",
"location":[32.052098, 76.649294]
}
}
}
}
}
響應
{
"took":6, "timed_out":false, "_shards":{"total":10, "successful":10, "failed":0},
"hits":{
"total":2, "max_score":1.0, "hits":[
{
"_index":"schools", "_type":"school", "_id":"2", "_score":1.0,
"_source":{
"name":"Saint Paul School", "description":"ICSE Affiliation",
"street":"Dawarka", "city":"Delhi", "state":"Delhi", "zip":"110075",
"location":[28.5733056, 77.0122136], "fees":5000,
"tags":["Good Faculty", "Great Sports"], "rating":"4.5"
}
},
{
"_index":"schools", "_type":"school", "_id":"1", "_score":1.0,
"_source":{
"name":"Central School", "description":"CBSE Affiliation",
"street":"Nagan", "city":"paprola", "state":"HP", "zip":"176115",
"location":[31.8955385, 76.8380405], "fees":2000,
"tags":["Senior Secondary", "beautiful campus"], "rating":"3.5"
}
}
]
}
}
注意 - 如果在執行上述範例時遇到異常，請將以下對映新增到索引。
{
"mappings":{
"school":{
"_all":{
"enabled":true
},
"properties":{
"location":{
"type":"geo_point"
}
}
}
}
}