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
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PUT /customer { "settings":{ "number_of_shards": 5, "number_of_replicas": 2 }, "mAppings":{ "properties":{ "name":{ "type":"text" }, "age":{ "type": "integer" } } } } |
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{ "acknowledged": true, "shards_acknowledged": true, "index": "customer" } |
2.删除索引
删除索引使用 DELETE /indexName
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DELETE /customer |
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{ "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。
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POST /customer/_close |
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{ "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。
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POST /customer/_open |
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{ "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：
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PUT /log-20230329 { "mappings": { "properties": { "title": { "type": "text" }, "content": { "type": "text" }, "code": { "type": "keyword" }, "info": { "type": "text" } } } } |
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POST /log-20230329/_doc/001 { "title": "日志29", "content":"内容29", "code": "0001", "info":"操作失败" } |
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PUT /log-20230328 |
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POST /log-20230328/_doc/001 { "title": "日志28", "content":"内容28", "code": "0000", "info":"操作成功" } |
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PUT /log-20230327 |
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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
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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" } } ] } |
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{ "acknowledged": true } |
这个时候查询last_three_day_log就会查询到关联的三个索引：
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GET /last_three_day_log/_search { "query":{ "match":{ "title":"日志" } } } |
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{ "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：
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PUT /log-20230330 { "mappings": { "properties": { "title": { "type": "text" }, "content": { "type": "text" }, "code": { "type": "keyword" }, "info": { "type": "text" } } } } |
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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
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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" } } ] } |
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{ "acknowledged": true } |
重新查询last_three_day_log就会发现没有log-20230327索引的内容了：
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GET /last_three_day_log/_search { "query":{ "match":{ "title":"日志" } } } |
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{ "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" } } ] } } |
