Elastic Search 命令详解-索引操作

关于Elastic Search安装可以参考《Elastic Search 8.6.2集群安装部署》及Kibana安装可以参考《Elastic Search 8.6.2简单操作》。相关命令将在Kibana工具的Console平台上执行。

Elastic Search索引操作主要包含：创建、删除、关闭和打开索引，以及索引别名的操作。其中，索引别名的操作在生产环境中使用比较广泛，可以和关闭或删除索引配合使用。在生产环境中使用索引时，都应该特别注意操作不当引起数据丢失或异常的问题。

1.创建索引

使用Elastic Search构建搜索引擎的第一步就是创建索引。创建索引以PUT方式发起请求，命令 PUT /indexName

PUT /customer {   "settings":{     "number_of_shards": 5,      "number_of_replicas": 2   },   "mappings":{     "properties":{       "name":{         "type":"text"       },       "age":{         "type": "integer"       }     }   } }

{   "acknowledged": true,   "shards_acknowledged": true,   "index": "customer" }

        

 

2.删除索引

删除索引使用 DELETE /indexName

DELETE /customer

{   "acknowledged": true }

3.关闭索引

有些索引可能在暂时不使用，但未来可能还会使用时，就可以关闭该索引。索引关闭时，只能使用Elastic Search的Api或者监控工具来查看该索引的信息。此时对索引的读写操作都会报错：索引关闭异常。

POST /customer/_close

{   "acknowledged": true,   "shards_acknowledged": true,   "indices": {     "customer": {       "closed": true     }   } }

4.打开索引

索引关闭了，想重新使用可以再次打开索引。

POST /customer/_open

{   "acknowledged": true,   "shards_acknowledged": true }

5.索引别名

索引别名一般是通过一个别名关联一个或多个索引，让别名与索引之间建立逻辑关系，以地区、时间等划分索引的场景会使用到。例如日志场景：

        

 

PUT /log-20230329 {   "mappings": {     "properties": {       "title": {         "type": "text"       },       "content": {         "type": "text"       },       "code": {         "type": "keyword"       },       "info": {         "type": "text"       }     }   } }

POST /log-20230329/_doc/001 {   "title": "日志29",   "content":"内容29",   "code": "0001",   "info":"操作失败" }

PUT /log-20230328

POST /log-20230328/_doc/001 {   "title": "日志28",   "content":"内容28",   "code": "0000",   "info":"操作成功" }

PUT /log-20230327

POST /log-20230327/_doc/001 {   "title": "日志27",   "content":"内容27",   "code": "0000",   "info":"操作成功" }

创建索引别名

POST /_aliases {   "actions": [     {       "add":{         "index": "log-20230329",         "alias": "last_three_day_log"       }     },{       "add":{         "index": "log-20230328",         "alias": "last_three_day_log"       }     },{       "add":{         "index": "log-20230327",         "alias": "last_three_day_log"       }     }   ] }

{   "acknowledged": true }

这个时候查询last_three_day_log就会查询到关联的三个索引：

GET /last_three_day_log/_search {   "query":{     "match":{       "title":"日志"     }   } }

{   "took": 6,   "timed_out": false,   "_shards": {     "total": 3,     "successful": 3,     "skipped": 0,     "failed": 0   },   "hits": {     "total": {       "value": 3,       "relation": "eq"     },     "max_score": 0.5753642,     "hits": [       {         "_index": "log-20230327",         "_id": "001",         "_score": 0.5753642,         "_source": {           "title": "日志27",           "content": "内容27",           "code": "0000",           "info": "操作成功"         }       },       {         "_index": "log-20230328",         "_id": "001",         "_score": 0.5753642,         "_source": {           "title": "日志28",           "content": "内容28",           "code": "0000",           "info": "操作成功"         }       },       {         "_index": "log-20230329",         "_id": "001",         "_score": 0.5753642,         "_source": {           "title": "日志29",           "content": "内容29",           "code": "0001",           "info": "操作失败"         }       }     ]   } }

数据是不能直接写到别名的索引，如果需要写入数据则需要在创建别名时添加参数 is_write_index。

别名除了关联多个索引实现组合查询外，还可以用来替换索引。实现原理很简单，例如：当天的日志已经生成了，现在近三天日志，应该将log-20230327删除，重新添加log-20230330的索引，就实现了替换索引，先创建log-20230330索引：

PUT /log-20230330 {   "mappings": {     "properties": {       "title": {         "type": "text"       },       "content": {         "type": "text"       },       "code": {         "type": "keyword"       },       "info": {         "type": "text"       }     }   } }

POST /log-20230330/_doc/001 {   "title": "日志30",   "content":"内容30",   "code": "0000",   "info":"操作成功" }

再重新定义索引别名

POST /_aliases {   "actions": [      {       "add":{         "index": "log-20230330",         "alias": "last_three_day_log"       }     },{       "add":{         "index": "log-20230329",         "alias": "last_three_day_log"       }     },{       "add":{         "index": "log-20230328",         "alias": "last_three_day_log"       }     },{       "remove":{         "index": "log-20230327",         "alias": "last_three_day_log"       }     }   ] }

{   "acknowledged": true }

重新查询last_three_day_log就会发现没有log-20230327索引的内容了：

GET /last_three_day_log/_search {   "query":{     "match":{       "title":"日志"     }   } }

{   "took": 11,   "timed_out": false,   "_shards": {     "total": 3,     "successful": 3,     "skipped": 0,     "failed": 0   },   "hits": {     "total": {       "value": 3,       "relation": "eq"     },     "max_score": 0.5753642,     "hits": [       {         "_index": "log-20230328",         "_id": "001",         "_score": 0.5753642,         "_source": {           "title": "日志28",           "content": "内容28",           "code": "0000",           "info": "操作成功"         }       },       {         "_index": "log-20230329",         "_id": "001",         "_score": 0.5753642,         "_source": {           "title": "日志29",           "content": "内容29",           "code": "0001",           "info": "操作失败"         }       },       {         "_index": "log-20230330",         "_id": "001",         "_score": 0.5753642,         "_source": {           "title": "日志30",           "content": "内容30",           "code": "0000",           "info": "操作成功"         }       }     ]   } }