什么是映射
類似於數據庫中的表結構定義，主要作用如下：
- 定義Index下字段名（Field Name）
- 定義字段的類型，比如數值型，字符串型、布爾型等
- 定義倒排索引的相關配置，比如是否索引、記錄postion等
需要注意的是，在索引中定義太多字段可能會導致索引膨脹，出現內存不足和難以恢復的情況，下面有幾個設置：
- index.mapping.total_fields.limit：一個索引中能定義的字段的最大數量，默認是 1000
- index.mapping.depth.limit：字段的最大深度，以內部對象的數量來計算，默認是20
- index.mapping.nested_fields.limit：索引中嵌套字段的最大數量，默認是50
Mapping的數據類型
基本數據類型
| 屬性名字 | 說明 |
| text | 用於全文索引，該類型的字段將通過分詞器進行分詞，最終用於構建索引 |
| keyword | 不分詞 |
| long | 有符號64-bit integer：-2^63 ~ 2^63 - 1 |
| integer | 有符號32-bit integer，-2^31 ~ 2^31 - 1 |
| short | 有符號16-bit integer，-32768 ~ 32767 |
| byte | 有符號8-bit integer，-128 ~ 127 |
| double | 64-bit IEEE 754 浮點數 |
| float | 32-bit IEEE 754 浮點數 |
| half_float | 16-bit IEEE 754 浮點數 |
| boolean | true,false |
| date | https://www.elastic.co/guide/en/elasticsearch/reference/current/mapping-date-format.html |
| binary | 該類型的字段把值當做經過 base64 編碼的字符串，默認不存儲，且不可搜索 |
Mapping范圍數據類型
標識一個數據范圍而不是一個值 如age:10~20 搜索{"gle":5,"lte":20} 則可以搜索出來數據
| 支持的數據類型 | 說明 |
| integer_range |
|
| float_range |
|
| long_range |
|
| double_range |
|
| date_range |
64-bit 無符號整數，時間戳（單位：毫秒） |
| ip_range |
IPV4 或 IPV6 格式的字符串 |
可選參數:
relation這只匹配模式
INTERSECTS 默認的匹配模式，只要搜索值與字段值有交集即可匹配到
WITHIN 字段值需要完全包含在搜索值之內，也就是字段值是搜索值的子集才搜索出來
CONTAINS 與WITHIN相反，只搜索字段值包含搜索值的文檔
測試
1.添加index
put:127.0.0.1:9200/range_test
{ "mappings": { "_doc": { "properties": { "count": { "type": "integer_range" }, "create_date": { "type": "date_range", "format": "yyyy-MM-dd HH:mm:ss||yyyy-MM-dd||epoch_millis" } } } } }
2.添加測試數據
post:127.0.0.1:9200/range_test/_doc/1
{ "count" : { "gte" : 1, "lte" : 100 }, "create_date" : { "gte" : "2019-02-1 12:00:00", "lte" : "2019-03-30" } }
3.測試搜索
get:127.0.0.1:9200/range_test/_doc/_search
{ "query":{ "term":{ "count":5 } } }
5在1~100之間可以搜索出來
{ "query" : { "range" : { "create_date" : { "gte" : "2019-02-01", "lte" : "2019-03-30", "relation" : "within" } } } }
Mapping復雜數據類型
數組類型 Array
支持字符串 數值 object對象數組 數組元素必須為相同數據類型
對象類型 Object
{ "name": "小明", "user_info": { "student_id": 111, "class_info": { "class_name": "1年級" } } }
被索引形式
{ "name":"小明", "user_info.student_id":"111", "user_info.student_info.class_name":"111" }
嵌套類型 Nested
能夠支持數組元素單獨的做索引
查詢api:https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-nested-query.html
聚合api:https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-bucket-reverse-nested-aggregation.html
排序api:https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-bucket-reverse-nested-aggregation.html
檢索和高亮:https://www.elastic.co/guide/en/elasticsearch/reference/current/search-request-inner-hits.html#nested-inner-hits
Nested和Object區別
put:127.0.0.1:9200/object_test/_doc/1 默認是object類型
{ "user_name":"小明", "subjects":[ {"subject_name":"地理","id":1}, {"subject_name":"英語","id":2} ] }
搜索名字為英語id為1的
{ "query":{ "bool":{ "must":[ {"match":{"subjects.subject_name":"英語"}}, {"match":{"subjects.id":"1"}} ] } } }
正常搜索不出來 測試時搜索出來了
因為索引為以下格式
{ "name":"小明", "subjects.subject_name":["英語","地理"], "subjects.subject_id":["1","2"] }
改為Nested 就不會
地理數據類型
geo_point
幾種格式
object對象："location": {"lat": 41.12, "lon": -71.34}
字符串："location": "41.12,-71.34"
geohash："location": "drm3btev3e86"
數組："location": [ -71.34, 41.12 ]
geo_shape
查詢api:https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-geo-bounding-box-query.html專用數據類型
- 記錄IP地址 ip
- 實現自動補全 completion
- 記錄分詞數 token_count
- 記錄字符串hash值 murmur3
- Percolator
Mapping設置
一個完整的mapping設置
{ "settings": { "analysis": { "analyzer": { "ik_pinyin_analyzer": { "type": "custom", "tokenizer": "ik_smart", "filter": ["my_pinyin"]#自定義filter }, "pinyin_analyzer": { "tokenizer": "shopmall_pinyin" }, "first_py_letter_analyzer": { "tokenizer": "first_py_letter" }, "full_pinyin_letter_analyzer": { "tokenizer": "full_pinyin_letter" }, "onlyOne_analyzer": { "tokenizer": "onlyOne_pinyin" } }, "tokenizer": {#自定義分詞器 "onlyOne_pinyin": { "type":"pinyin", "keep_separate_first_letter": "false", "keep_first_letter":"false" }, "shopmall_pinyin": { "keep_joined_full_pinyin": "true", "keep_first_letter": "true", "keep_separate_first_letter": "false", "lowercase": "true", "type": "pinyin", "limit_first_letter_length": "16", "keep_original": "true", "keep_full_pinyin": "true", "keep_none_chinese_in_joined_full_pinyin": "true" }, "first_py_letter": { "type": "pinyin", "keep_first_letter": true, "keep_full_pinyin": false, "keep_original": false, "limit_first_letter_length": 16, "lowercase": true, "trim_whitespace": true, "keep_none_chinese_in_first_letter": false, "none_chinese_pinyin_tokenize": false, "keep_none_chinese": true, "keep_none_chinese_in_joined_full_pinyin": true }, "full_pinyin_letter": { "type": "pinyin", "keep_separate_first_letter": false, "keep_full_pinyin": false, "keep_original": false, "limit_first_letter_length": 16, "lowercase": true, "keep_first_letter": false, "keep_none_chinese_in_first_letter": false, "none_chinese_pinyin_tokenize": false, "keep_none_chinese": true, "keep_joined_full_pinyin": true, "keep_none_chinese_in_joined_full_pinyin": true } }, "filter": { "my_pinyin": { "type": "pinyin", "keep_joined_full_pinyin": true, "keep_separate_first_letter":true } } } }, "mappings": { "doc": {#type名字 "properties": {#mapping的屬性 "productName": {屬性名字 "type": "text",#屬性類型 "analyzer": "ik_pinyin_analyzer",#分詞器 "fields": {#fields 指定自定義分詞器 查詢時通過productName.keyword_once_pinyin 可以指定 "keyword_once_pinyin": { "type": "text", "analyzer": "onlyOne_analyzer"#指定的自定義分詞器 } } }, "skuNames": { "type": "text", "analyzer": "ik_pinyin_analyzer", "fields": { "keyword_once_pinyin": { "type": "text", "analyzer": "onlyOne_analyzer" } } }, "regionCode": { "type": "keyword" }, "productNameSuggester": {#es6.x搜索建議實現 "type": "completion", "fields": { "pinyin": { "type": "completion", "analyzer": "pinyin_analyzer" }, "keyword_pinyin": { "type": "completion", "analyzer": "full_pinyin_letter_analyzer" }, "keyword_first_py": { "type": "completion", "analyzer": "first_py_letter_analyzer" } } } "info": {#es6父子類型設置 "type": "join", "relations": { "md_product":[ "sl_customer_character_order_list","ic_product_store_account","sl_customer_product_setting"] } } } } } }
創建mapping
put:http://127.0.0.1:9200/db
{
"mappings": { "product": {//type "properties": { "productName": {//字段 "type": "text"//數據類型 } } } } }
mapping參數
| 參數 | 說明 |
| analyzer | 分詞器 默認:standard |
| boost | 字段權重默認1 在通過_all字段查詢 根據此字段來權重 |
| dynamic | 控制字段新增 true(默認 允許新增) false strict 不能新增文檔 |
| index | 控制字段是否索引(可搜索) true 是 false否 |
參考:https://www.jianshu.com/p/e8a9feea683c
新增mapping字段
Elasticsearch的mapping一旦創建，只能增加字段，而不能修改已經mapping的字段
put http://127.0.0.1:9200/{indexName}/_mapping/{typeName} { "properties": { "productSortItemIds": { #字段名字 "type": "string",#類型 "store": true, #是否持久化 "analyzer": "comma", #分詞器 "search_analyzer": "comma" #搜索分詞器 } } }
新增分詞器
post /{index}/_close #關閉索引
put /bbc_product/_settings #增加,號分詞器
{
"settings": {
"analysis": {
"analyzer": {
"comma": {
"type": "pattern",
"pattern":","
}
}
}
}
}
post /{index}/_open #開啟索引
查看當前索引的映射
http://127.0.0.1:9200/blogs2/product/_mapping 不加/_mapping可看整個index設置
{
"blogs2": { "mappings": { "product": { "properties": { "price": { "type": "long" }, "productName": { "type": "text", "fields": { "keyword": { "type": "keyword", "ignore_above": 256 } } }, "remark": { "type": "text", "fields": { "keyword": { "type": "keyword", "ignore_above": 256 } } }, "tags": { "type": "text", "fields": { "keyword": { "type": "keyword", "ignore_above": 256 } } } } } } } }
自定義映射
作用定義數據類型 比如數字映射成text 大於小於范圍搜索就會無效 還有明確哪些fullText需要分詞哪些不需要分詞
確切值(Exact values)和全文本(FullText)
es支持很多種數據類型但是主要分為2大類
確切值就是能夠確定的值 比如id 日期 通過=就能查詢到我們想要的數據
而全文本是需要進行相似度匹配 返回最佳匹配