es 集群健康状态 es 查询集群健康状态 1 2 3 4 5 6 7 8 9 10 GET /_cat/health?v epoch timestamp cluster status node.total node.data shards pri relo init unassign pending_tasks max_task_wait_time active_shards_percent 1488006741 15:12:21 elasticsearch yellow 1 1 1 1 0 0 1 0 - 50.0% epoch timestamp cluster status node.total node.data shards pri relo init unassign pending_tasks max_task_wait_time active_shards_percent 1488007113 15:18:33 elasticsearch green 2 2 2 1 0 0 0 0 - 100.0% epoch timestamp cluster status node.total node.data shards pri relo init unassign pending_tasks max_task_wait_time active_shards_percent 1488007216 15:20:16 elasticsearch yellow 1 1 1 1 0 0 1 0 - 50.0%
集群健康状态 green、yellow、red
green：每个索引的primary shard和replica shard都是active状态的
yellow：每个索引的primary shard都是active状态的，但是部分replica shard不是active状态，处于不可用的状态
red：不是所有索引的primary shard都是active状态的，部分索引有数据丢失了
为什么会会处于yellow状态？ 比如当前es只有一台服务启动即只有一个node，此时只启动了一个primary shard，而依据es的 容错机制 replica shard 不予 primary shard 同服务，即单机情况下 集群状态为yellow
es 基础操作 查询集群下的 索引 1 2 3 4 5 GET /_cat/indices?v health status index uuid pri rep docs.count docs.deleted store.size pri.store.size yellow open student rUm9n9wMRQCCrRDEhqneBg 1 1 1 0 3.1kb 3.1kb
新建索引 删除索引 索引的 CURD
新建搜索内容 document注意: 当PUT作为update操作时，需要将所有filed全部写上，否则全覆盖，一般不建议用于update
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 PUT /student/class/1 { "name":"tom" "age":15 } //数据下面有用到 PUT /student/class/2 { "name":"ajo" "age":20 } PUT /student/class/3 { "name":"jack" "age":25 }
1 2 3 4 5 6 7 PUT /student/class/1/_update { "doc":{ "name":"jack" } }
删除指定搜索内容1 2 DELETE /student/class/1
es 查询操作相关
即返回结果为 document id 为1、2的数据
1 2 3 4 5 6 7 8 9 GET /student/class/_search { "query":{ "match":{ "name":"tom" } } }
phrase search 短语查询
1 2 3 4 5 6 7 8 9 GET /student/class/_search { "query":{ "match_phrase":{ "name":"tom" } } }
查询条件
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 GET /student/class/_search { "query":{ "bool": { "filter": [ {"range": { "ago": { "gte": 10,//大于等于 "lte": 20//小于等于 } }} ] } } }
highlight search（高亮搜索结果）
1 2 3 4 5 6 7 8 9 10 11 12 13 GET /ecommerce/product/_search { "query" : { "match" : { "producer" : "producer" } }, "highlight": { "fields" : { "producer" : {} } } }
mget批量查询api mget批量查询可以将多个操作合并一个读操作去执行，可以减少网络请求次数，提升系统性能，当然如果请求数据过多，也会在一定程度上影响了影响速度
场景1 不同index下 的查询
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 GET /_mget { "docs" : [ { "_index" : "test_index1", "_type" : "test_type", "_id" : 1 }, { "_index" : "test_index2", "_type" : "test_type", "_id" : 2 } ] }
场景2 同一index下 的查询
1 2 3 4 GET /test_index/type/_mget { "ids": [1, 2] }
批量写操作 _bulk bulk api对json的语法有严格要求，每个json串不能换行，只能放一行，同时一个json串和一个json串之间，必须有一个换行，bulk 的语法格式如下
1 2 {"action": {"metadata"}} {"data"}
bulk 主要支持一下类型的操作：
delete: 删除一个文档，只要1个json串就可以了
create: PUT /index/type/id/_create，强制创建
index：普通的put操作，可以是创建文档，也可以是全量替换文档
update：执行的partial update操作
1 2 3 4 5 6 7 8 POST /_bulk { "delete": { "_index": "test_index", "_type": "test_type", "_id": "3" }} { "create": { "_index": "test_index", "_type": "test_type", "_id": "12" }} { "test_field": "test12" } { "index": { "_index": "test_index", "_type": "test_type", "_id": "2" }} { "test_field": "replaced test2" } { "update": { "_index": "test_index", "_type": "test_type", "_id": "1", "_retry_on_conflict" : 3} } { "doc" : {"test_field2" : "bulk test1"} }
bulk 操作出现异常 bulk操作中，任意一个操作失败，是不会影响其他的操作，但是会在返回的结果里面告诉异常日志
bulk 性能 bulk request会加载到内存里，如果太大的话，性能反而会下降，需要反复尝试得出一个最佳的bulk size，一般从1000-5000条数据开始，尝试逐渐增加
分页查询 分页主要有两个参数起始页为0 为0 与不传from 单传size效果一致
请求方式主要有：
script 1 2 3 GET _search?size=2 GET _search?size=2&from=0 # 返回结果与第一条执行结果一致 GET _search?size=2&from=2
deep paging 问题 集群环境下，当查询的目标数据很多，比如超过几十万甚至几百万数据时，这个时候进行分页，这个时候:
step1 client 分页请求 如 _search?size=1000&from=1000000 到 coordinate node ,节点会找到该查询多个对应的shard（假设3shard）
step2 请求到达对应的shard 开始执行分页操作 _search?size=1000&from=1000000 取1000条数据 并返回给coordinate node
step3 coordinate收到shard返回的总数据条数为3000条，这个时候开始做重排序，默认是通过相关度分数排序 ,取前1000条数据返回给client
deep paging问题 其实是一个深度查询的问题，如涉及分页查询较深时且数据较大时，非常消耗网络带宽，消耗内存，所以存在性能问题，应尽量避免 deep paging操作
多种搜索方式 query string search query string search的由来：
（1）搜索所有的商品：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 GET /sell/product/_search 返回值： { "took": 12, "timed_out": false, "_shards": { "total": 5, "successful": 5, "failed": 0 }, "hits": { "total": 3, "max_score": 1, "hits": [ { "_index": "sell", "_type": "product", "_id": "2", "_score": 1, "_source": { "name": "oyr yaogao", "desc": "zheshi oyr yagao", "price": 3000, "producer": "oyr yagao producer", "tags": [ "lengcang", "baoxian" ] } }, { "_index": "sell", "_type": "product", "_id": "1", "_score": 1, "_source": { "name": "gaolujie yagao", "desc": "zheshi gaolujie yigeyagao", "price": 30, "producer": "gaolujie yagao producer", "tags": [ "meibai", "fangzhu" ] } }, { "_index": "sell", "_type": "product", "_id": "3", "_score": 1, "_source": { "name": "latiao", "desc": "zheshi latiao yagao", "price": 15, "producer": "latiao yagao producer", "tags": [ "la", "meiwei" ] } } ] } }
返回值说明：
（2）搜索商品名称中包含yagao的商品，而且按照售价降序排序
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 GET /sell/product/_search?q=name:yagao&sort=price:desc 返回值： { "took": 2, "timed_out": false, "_shards": { "total": 5, "successful": 5, "failed": 0 }, "hits": { "total": 3, "max_score": null, "hits": [ { "_index": "sell", "_type": "product", "_id": "2", "_score": null, "_source": { "name": "oyr yagao", "desc": "zheshi oyr yagao", "price": 3000, "producer": "oyr yagao producer", "tags": [ "lengcang", "baoxian" ] }, "sort": [ 3000 ] }, { "_index": "sell", "_type": "product", "_id": "1", "_score": null, "_source": { "name": "gaolujie yagao", "desc": "zheshi gaolujie yigeyagao", "price": 30, "producer": "gaolujie yagao producer", "tags": [ "meibai", "fangzhu" ] }, "sort": [ 30 ] }, { "_index": "sell", "_type": "product", "_id": "3", "_score": null, "_source": { "name": "latiao yagao", "desc": "zheshi latiao yagao", "price": 15, "producer": "latiao yagao producer", "tags": [ "la", "meiwei" ] }, "sort": [ 15 ] } ] } }
query DSL DSL：Domain Specified Language，特定领域的语言
（1）查询所有的商品
1 2 3 4 5 6 GET /sell/product/_search { "query": { "match_all": {} } }
（2）查询名称包含yagao的商品，同时按照价格降序排序
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 GET /sell/product/_search { "query": { "match": { "name": "yagao" } } , "sort": [ { "price": "desc" } ] } 或 GET /sell/product/_search { "query": { "match": { "name": "yagao" } }, "sort": [ { "price": { "order": "desc" } } ] }
（3）分页查询商品，总共3条商品，假设每页就显示1条商品，现在显示第2页，所以就查出来第2个商品
1 2 3 4 5 6 7 8 GET /sell/product/_search { "query": { "match_all": {} }, "from": 1, // 从第一条开始查,并不包含第一条 "size": 1 // 查一条数据 }
（4）指定要查询出来商品的名称和价格就可以，也就是具体要显示哪些field。
1 2 3 4 5 6 7 GET /sell/product/_search { "query": { "match_all": {} }, "_source": ["name", "price"] }
query filter （1）搜索商品名称包含yagao，而且售价大于25元的商品
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 GET /sell/product/_search { "query": { "bool": { "must": { "match": { "name": "yagao" } }, "filter": { "range": { "price": { "gt": 25 } } } } } }
full-text search 全文检索
1 2 3 4 5 6 7 8 GET /sell/product/_search { "query": { "match": { "producer": "oyr yagao producer" } } }
producer这个字段，会先被分词拆解
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 返回值： { "took": 2, "timed_out": false, "_shards": { "total": 5, "successful": 5, "failed": 0 }, "hits": { "total": 3, "max_score": 0.7594807, "hits": [ { "_index": "sell", "_type": "product", "_id": "2", "_score": 0.7594807, "_source": { "name": "oyr yagao", "desc": "zheshi oyr yagao", "price": 3000, "producer": "oyr yagao producer", "tags": [ "lengcang", "baoxian" ] } }, { "_index": "sell", "_type": "product", "_id": "1", "_score": 0.5063205, "_source": { "name": "gaolujie yagao", "desc": "zheshi gaolujie yigeyagao", "price": 30, "producer": "gaolujie yagao producer", "tags": [ "meibai", "fangzhu" ] } }, { "_index": "sell", "_type": "product", "_id": "3", "_score": 0.5063205, "_source": { "name": "latiao yagao", "desc": "zheshi latiao yagao", "price": 15, "producer": "latiao yagao producer", "tags": [ "la", "meiwei" ] } } ] } }
phrase search 短语搜索
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 GET /sell/product/_search { "query": { "match_phrase": { "producer": "oyr yagao producer" } } } 返回值： { "took": 15, "timed_out": false, "_shards": { "total": 5, "successful": 5, "failed": 0 }, "hits": { "total": 1, "max_score": 0.7594808, "hits": [ { "_index": "sell", "_type": "product", "_id": "2", "_score": 0.7594808, "_source": { "name": "oyr yagao", "desc": "zheshi oyr yagao", "price": 3000, "producer": "oyr yagao producer", "tags": [ "lengcang", "baoxian" ] } } ] } }
聚合查询 （1）计算每个tag下的商品数量
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 PUT /sell/_mapping/product { "properties": { "tags":{ "type": "text", "fielddata": true } } } 查询： GET /sell/product/_search { "size": 0, "aggs": { "group_by_tags": { "terms": { "field": "tags" } } } }
类似于数据库sql:
1 Select tags, count (* ) from product group by tags
返回值：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 { "took": 2, "timed_out": false, "_shards": { "total": 5, "successful": 5, "failed": 0 }, "hits": { "total": 3, "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 }, { "key": "meiwei", "doc_count": 2 }, { "key": "fangzhu", "doc_count": 1 } ] } } }
（2）对名称中包含yagao的商品，计算每个tag下的商品数量
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 GET /sell/product/_search { "size": 0, "query": { "match": { "name": "yagao" } }, "aggs": { "group_by_tags": { "terms": { "field": "tags" } } } }
类似于数据库sql:
1 Select tags, count (* ) from product where name= 'yagao' group by tags
返回值：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 { "took": 2, "timed_out": false, "_shards": { "total": 5, "successful": 5, "failed": 0 }, "hits": { "total": 3, "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 }, { "key": "meiwei", "doc_count": 2 }, { "key": "fangzhu", "doc_count": 1 } ] } } }
（3）先分组，再算每组的平均值，计算每个tag下的商品的平均价格
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 GET /sell/product/_search { "size": 0, "aggs": { "group_by_tags": { "terms": { "field": "tags" }, "aggs": { "avg_price": { "avg": {"field": "price"} } } } } }
类似于数据库sql:
1 Select tags, count (* ), avg (price) from product group by tags
返回值：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 { "took": 2, "timed_out": false, "_shards": { "total": 5, "successful": 5, "failed": 0 }, "hits": { "total": 3, "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": 1515 } }, { "key": "meiwei", "doc_count": 2, "avg_price": { "value": 1507.5 } }, { "key": "fangzhu", "doc_count": 1, "avg_price": { "value": 30 } } ] } } }
（4）计算每个tag下的商品的平均价格，并且按照平均价格降序排序
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 GET /sell/product/_search { "size": 0, "aggs": { "group_by_tags": { "terms": { "field": "tags", "order": { "avg_price": "desc" } }, "aggs": { "avg_price": { "avg": {"field": "price"} } } } } }
类似于数据库sql:
1 Select tags, count (* ), avg (price) as avg_price from product group by tags order by avg_price
返回值：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 { "took": 2, "timed_out": false, "_shards": { "total": 5, "successful": 5, "failed": 0 }, "hits": { "total": 3, "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": 1515 } }, { "key": "meiwei", "doc_count": 2, "avg_price": { "value": 1507.5 } }, { "key": "fangzhu", "doc_count": 1, "avg_price": { "value": 30 } } ] } } }
（5）按照指定的价格范围区间进行分组，然后在每组内再按照tag进行分组，最后再计算每组的平均价格
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 GET /sell/product/_search { "size": 0, "aggs": { "group_by_price": { "range": { "field": "price", "ranges": [ { "from": 0, "to": 20 }, { "from": 20, "to": 10000 } ] }, "aggs": { "group_by_tags": { "terms": { "field": "tags" }, "aggs": { "avg_price": { "avg": { "field": "price" } } } } } } } }
返回值：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 { "took": 3, "timed_out": false, "_shards": { "total": 5, "successful": 5, "failed": 0 }, "hits": { "total": 3, "max_score": 0, "hits": [] }, "aggregations": { "group_by_price": { "buckets": [ { "key": "0.0-20.0", "from": 0, "to": 20, "doc_count": 1, "group_by_tags": { "doc_count_error_upper_bound": 0, "sum_other_doc_count": 0, "buckets": [ { "key": "meiwei", "doc_count": 1, "avg_price": { "value": 15 } } ] } }, { "key": "20.0-10000.0", "from": 20, "to": 10000, "doc_count": 2, "group_by_tags": { "doc_count_error_upper_bound": 0, "sum_other_doc_count": 0, "buckets": [ { "key": "meibai", "doc_count": 2, "avg_price": { "value": 1515 } }, { "key": "fangzhu", "doc_count": 1, "avg_price": { "value": 30 } }, { "key": "meiwei", "doc_count": 1, "avg_price": { "value": 3000 } } ] } } ] } } }
filter 与 query的深入比较 filter与query示例 script 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 PUT /company/employee/2 { "address": { "country": "china", "province": "jiangsu", "city": "nanjing" }, "name": "tom", "age": 30, "join_date": "2016-01-01" } PUT /company/employee/3 { "address": { "country": "china", "province": "shanxi", "city": "xian" }, "name": "marry", "age": 35, "join_date": "2015-01-01" } # 搜索请求：年龄必须大于等于30，同时join_date必须是2016-01-01 GET /company/employee/_search { "query": { "bool": { "must": [ { "match": { "join_date": "2016-01-01" } } ], "filter": { "range": { "age": { "gte": 30 } } } } } }
filter 与 query对比
filter: 仅仅只是按搜索条件过滤出所需要的数据而已，不涉及相关度分数的计算，对相关度没有影响
query： 会去计算每个document相对搜索条件的相关度，并按相关度进行排序
总结：
如果是在进行搜索，需要将最匹配搜索条件的数据先返回，那么用query。
如果只是想根据搜索条件筛选出一部分数据，那么用filter
如果需要将符合条件的document排名靠前，用query包含，如果想其他的条件不影响到前面的document排序则用filter过滤
filter与query性能
filter： 不需要计算相关度分数，不需要按照相关度分数进行排序，同时还有内置的自动cache最常使用filter的数据
query： 相反，要计算相关度分数，按照分数进行排序，而且无法cache结果
单执行filter需注意 script 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 # 参数 constant_score 必传 否则会出现异常 GET /student/class/_search { "query": { "constant_score": { "filter": { "range": { "mark": { "gte": 30 } } } } } }
几种query的搜索语法 match all 查询所有
script 1 2 3 4 5 6 7 # 查询所有index的内容 GET /_search { "query": { "match_all": {} } }
script 1 2 3 4 5 6 7 # 查询指定index下的所有内容 GET student/class/_search { "query":{ "match_all": {} } }
match 匹配某一个filed是否包含某个文本，会触发分词，相当于是 full text(全文检索)
script 1 2 3 4 5 6 7 8 9 # 查询所有index 指定field是否包含查询内容 GET /_search { "query":{ "match": { "title": "学习" } } }
script 1 2 3 4 5 6 7 8 9 # 查询指定index 指定field是否包含查询内容 GET student/class/_search { "query":{ "match": { "title": "学习" } } }
multi match 查询多个field是否包含查询内容
script 1 2 3 4 5 6 7 8 9 10 # 查询所有index 指定的fields下是否包含查询内容 GET /_search { "query":{ "multi_match":{ "query":"学习", "fields":["title","desc"] } } }
script 1 2 3 4 5 6 7 8 9 10 11 # 查询指定index 指定的fields下是否包含查询内容 GET student/class/_search { "query":{ "multi_match":{ "query":"学习", "fields":["title","desc"] } } }
range query 查询field是否在指定的范围值内，放query里会对相关度产生影响，放filter里面无影响
script 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 # 查询所有index 指定的field是否在查询内容范围内 GET /_search { "query":{ "range":{ "mark":{ #"gt":80, 大于 #"lt":120 小于 "gte":80, #大于等于 "lte":120 #小于等于 } } } }
script 1 2 3 4 5 6 7 8 GET student/class/_search { "query":{ "range":{ "mark":{"gte":80} } } }
term query 把查询的数据当成 exact value（精准匹配）进行查询。field不分词 才能查询到最小分词单位
script 1 2 3 4 5 6 7 8 GET /_search { "query":{ "term": { "name": "八" } } }
script 1 2 3 4 5 6 7 8 GET student/class/_search { "query":{ "term": { "name": "八" } } }
terms query 原理与term一致，不过对指定的field可以查询指定多个搜索词
script 1 2 3 4 5 6 7 8 GET student/class/_search { "query":{ "terms": { "name": ["八","九"] } } }
组合查询 参数 bool 多条件组合查询参数，bool中可以使用 must、 must_not 、should 来组合查询条件 ,bool 可嵌套
must: 需要满足条件 ==或like
must_not: 不需要在满足条件内的 !=或 not like
should: should中的两个条件至少满足一个就可以,should下有多个条件时注意加参数 minimum_should_match
filter
script 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 # 查询学习成绩在30~100的学生信息，成绩倒叙，备注含学习,李四作弊取消成绩 GET student/class/_search?sort=mark:desc { "query":{ "bool": { "must_not": [ {"match": { "name": "李四" }} ], "minimum_should_match":2, # should下满足几个条件 "should": [ {"match":{"title":"委员"}} , {"match":{"desc":"突出"}} ], "filter": { "bool": { "must": [ {"range":{"mark": {"gte":20,"lte":100}}}, {"match":{"desc": "学习"}} ] } } } } }
校验不合法的搜索 特别复杂庞大的搜索下，比如你一下子写了上百行的搜索，这个时候可以先用validate api去验证一下，搜索是否合法
script 1 2 3 4 5 6 7 # 格式: GET index/type /_validate/query?explain GET student/class/_validate/query?explain { "query":{ "match_all": {} } }
返回结果
script 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 { "_shards" : { "total" : 1, "successful" : 1, "failed" : 0 }, "valid" : true, "explanations" : [ { "index" : "student", "valid" : true, "explanation" : "+*:* #*:*" } ] }
