elasticsearch
Posted liyingchun
tags:
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文章借鉴，原文链接https://www.dubby.cn/detail.html?id=9077
基础语法
1、使用工具
postman
2、索引创建
PUT http://127.0.0.1:9200/people/
{ "settings":{ "number_of_shards":3,//分片数，默认为5 "number_of_replicas":1 //备份数 },
//settings可以不设置，默认即可
//构建结构化索引，映射 "mappings":{ "person":{ //结构类型 "properties":{//设置属性 "name":{ "type":"text" //数据类型 }, "age":{ "type":"integer" }, "sex":{ "type":"text" }, "birthday":{ "type":"date", "format":"yyyy-MM-dd HH:mm:ss || yyyy-MM-dd || epoch_millis" //epoch_millis 时间戳
},
"country":{
"type":"keyword"
}
}
}
}
}
3、插入数据
PUT http://127.0.0.1:9200/people/person/1
{
"name":"lyc",
"sex":"男",
"birthday":"1993-01-20",
"country":"中国",
"age":20
}
这个URI后面的1代表的是这条数据的ID，也可以字符串。如果不想自己指定ID，可以不传，但是必须使用POST来新增，这样的话Elasticsearch会给这条数据生成一个随机的字符串。
如果想对这条数据进行更新，可以重新请求这个URI，关键是这个ID要指定，然后修改json内容，这样就可以更新这条数据了。
4、检索数据
根据ID检索某条具体数据：GET http://127.0.0.1:9200/people/person/1
查询效果：
{
"_index": "people",
"_type": "person",
"_id": "1",
"_version": 1,
"found": true,
"_source": {
"name": "lyc",
"sex": "男",
"birthday": "1993-01-20",
"country": "中国",
"age": 20
}
}
其中 _source就是我们存储的数据信息，若将请求方法GET改为DELETE，则删除这条数据
5、最简单的搜索
GET http://127.0.0.1:9200/people/_search
结果：
{
"took": 9,
"timed_out": false,
"_shards": {
"total": 3,
"successful": 3,
"skipped": 0,
"failed": 0
},
"hits": {
"total": 2,
"max_score": 1,
"hits": [
{
"_index": "people",
"_type": "person",
"_id": "2",
"_score": 1,
"_source": {
"name": "lyc",
"sex": "男",
"birthday": "1993-01-20",
"country": "中国",
"age": 18
}
},
{
"_index": "people",
"_type": "person",
"_id": "1",
"_score": 1,
"_source": {
"name": "nini",
"sex": "女",
"birthday": "1995-01-20",
"country": "中国",
"age": 18
}
}
]
}
}
搜索指定Index下的Type的全部文档，默认每页只显示10条，可以通过size字段改变这个设置，还可以通过from字段，指定位移（默认是从位置0开始）。返回结果的 took字段表示该操作的耗时（单位为毫秒），timed_out字段表示是否超时，hits字段表示命中的记录
6、简单条件搜索
查询name为lyc的数据
GET http://127.0.0.1:9200/people/_search?q=name:lyc
7、条件搜索
POST http://127.0.0.1:9200/people/_search
参数：
{
"query" : {
"match" : {
"name" : "nini"
}
}
}
结果：
{
"took": 9,
"timed_out": false,
"_shards": {
"total": 3,
"successful": 3,
"skipped": 0,
"failed": 0
},
"hits": {
"total": 1,
"max_score": 0.2876821,
"hits": [
{
"_index": "people",
"_type": "person",
"_id": "1",
"_score": 0.2876821,
"_source": {
"name": "nini",
"sex": "女",
"birthday": "1995-01-20",
"country": "中国",
"age": 18
}
}
]
}
}
这段查询和上面的例子是一样的，不过参数从简单的参数变成了一个复杂的json，不过复杂带来的优势就是控制力更强，我们可以对查询做出更多精细的控制。
8、更复杂的搜索
POST http://127.0.0.1:9200/people/_search
{
"query" : {
"bool": {
"must": {
"match" : {
"name" : "nini"
}
},
"filter": {
"range" : {
"age" : { "gt" : 10 }
}
}
}
}
}
这里新增了一个range过滤器，gt 表示_大于(_great than)
9、全文搜索
POST http://127.0.0.1:9200/people/_search
{
"query" : {
"match" : {
"name" : "nini lyc"
}
}
}
搜索name中包含nini 或 lyc字眼的数据，若是精确匹配，则将match改为match_phrase
10、高亮搜索
POST http://127.0.0.1:9200/people/_search
{
"query" : {
"match" : {
"name" : "nini lyc"
}
},
"highlight": {
"fields" : {
"name" : {}
}
}
}
结果：
{ "took": 96, "timed_out": false, "_shards": { "total": 3, "successful": 3, "skipped": 0, "failed": 0 }, "hits": { "total": 2, "max_score": 0.2876821, "hits": [ { "_index": "people", "_type": "person", "_id": "2", "_score": 0.2876821, "_source": { "name": "lyc", "sex": "男", "birthday": "1993-01-20", "country": "中国", "age": 18 }, "highlight": { "name": [ "<em>lyc</em>" ] } }, { "_index": "people", "_type": "person", "_id": "1", "_score": 0.2876821, "_source": { "name": "nini", "sex": "女", "birthday": "1995-01-20", "country": "中国", "age": 18 }, "highlight": { "name": [ "<em>nini</em>" ] } } ] } }
返回结果多了个highlight的部分，默认是用<em></em>包裹
11、简单聚合
在聚合之前，需要做些修改，因为Elasticsearch默认是不支持对text类型的数据聚合的，所以需要先开启"fielddata": true
PUT http://127.0.0.1:9200/people/
{
"settings":{
"number_of_shards":3,
"number_of_replicas":1
},
"mappings":{
"person":{
"properties":{
"name":{
"fielddata": true,
"type":"text"
},
"age":{
"type":"integer"
},
"sex":{
"type":"text"
},
"birthday":{
"type":"date",
"format":"yyyy-MM-dd HH:mm:ss || yyyy-MM-dd || epoch_millis"
},
"country":{
"type":"keyword"
}
}
}
}
}
按照name聚合
POST http://127.0.0.1:9200/people/_search
{
"aggs": {
"all_interests": {
"terms": { "field": "name" }
}
}
}
结果：
{
"took": 25,
"timed_out": false,
"_shards": {
"total": 3,
"successful": 3,
"skipped": 0,
"failed": 0
},
"hits": {
"total": 3,
"max_score": 1,
"hits": [
{
"_index": "people",
"_type": "person",
"_id": "2",
"_score": 1,
"_source": {
"name": "liyingchun",
"sex": "男",
"birthday": "1993-01-20",
"country": "中国",
"age": 20
}
},
{
"_index": "people",
"_type": "person",
"_id": "1",
"_score": 1,
"_source": {
"name": "lyc",
"sex": "男",
"birthday": "1993-01-20",
"country": "中国",
"age": 20
}
},
{
"_index": "people",
"_type": "person",
"_id": "3",
"_score": 1,
"_source": {
"aggs": {
"all_interests": {
"terms": {
"field": "name"
}
}
}
}
}
]
},
"aggregations": {
"all_interests": {
"doc_count_error_upper_bound": 0,
"sum_other_doc_count": 0,
"buckets": [
{
"key": "liyingchun",
"doc_count": 1
},
{
"key": "lyc",
"doc_count": 1
}
]
}
}
}
过滤后聚合
{
"query": {
"match": {
"name": "lyc"
}
},
"aggs": {
"all_interests": {
"terms": { "field": "name" }
}
}
}
结果：
{
"_index": "people",
"_type": "person",
"_id": "3",
"_version": 4,
"result": "deleted",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 8,
"_primary_term": 1
}
12、计数
POST http://127.0.0.1:9200/_count
{
"query": {
"match_all": {}
}
}
结果：
{
"count": 2,
"_shards": {
"total": 3,
"successful": 3,
"skipped": 0,
"failed": 0
}
}
对某个type计数
POST http://127.0.0.1:9200/people/person
{
"query": {
"name" : "lyc"
}
}
结果：
{
"_index": "people",
"_type": "person",
"_id": "9-31KGYBiQSwQuaX7D-s",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"_seq_no": 0,
"_primary_term": 1
}
13、集群健康
GET http://127.0.0.1:9200/_cluster/health
结果：
{
"cluster_name": "liyingchun",
"status": "green",
"timed_out": false,
"number_of_nodes": 2,
"number_of_data_nodes": 2,
"active_primary_shards": 3,
"active_shards": 6,
"relocating_shards": 0,
"initializing_shards": 0,
"unassigned_shards": 0,
"delayed_unassigned_shards": 0,
"number_of_pending_tasks": 0,
"number_of_in_flight_fetch": 0,
"task_max_waiting_in_queue_millis": 0,
"active_shards_percent_as_number": 100
}
14、监控单个节点
GET http://127.0.0.1:9200/_nodes/stats
15、集群统计
GET http://127.0.0.1:9200/_cluster/stats
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