Elasticsearch 更新字段映射 mapping

Elasticsearch 不支持现有字段映射更新。可以通过正确创建映射一个新的索引，然后将原索引上的数据复制到新的索引上，再将 alias 指向新 indices。然后再删除原索引。

1. 将原索引 test 添加 alias

   curl -X POST "http://192.168.1.101:9200/_aliases?pretty" -H 'Content-Type: application/json' -d'
   {
     "actions": [
       {
         "add": {
           "index": "test_source",
           "alias": "test"
         }
       }
     ]
   }
   '
   

   或

   curl -X PUT "http://192.168.1.101:9200/test_source/_alias/test?pretty"
   

2. 创建新索引 test_new

   curl -X PUT "http://192.168.1.101:9200/test_new?pretty"
   curl -X POST "http://192.168.1.101:9200/test_new/_mapping?pretty" -H 'Content-Type: application/json' -d'
   {
       "properties": {
           "title": {
               "type": "text",
               "analyzer":"ik_max_word",
               "search_analyzer":"ik_smart"
           },
           "content": {
               "type": "text",
               "analyzer":"ik_max_word",
               "search_analyzer":"ik_smart"
           },
           "author": {
               "type": "keyword"
           },
           "category": {
               "type": "keyword"
           }
       }
   }
   '
   

   查看原索引 mapping

   curl -X GET "http://192.168.1.101:9200/test_source/_mapping?pretty"
   {
     "test_source" : {
       "mappings" : {
         "properties" : {
           "author" : {
             "type" : "keyword"
           },
           "category" : {
             "type" : "keyword"
           },
           "content" : {
             "type" : "text"
           },
           "title" : {
             "type" : "text"
           }
         }
       }
     }
   }
   

3. 从原索引复制数据到新索引

   注意: 不宜用于复制数据量过大的索引

   curl -X POST "http://192.168.1.101:9200/_reindex?pretty" -H 'Content-Type: application/json' -d'
   {
     "source": {
       "index": "test_source"
     },
     "dest": {
       "index": "test_new"
     }
   }
   '
   

4. 修改别名

   curl -X POST "http://192.168.1.101:9200/_aliases?pretty" -H 'Content-Type: application/json' -d'
   {
     "actions": [
       {
           "remove" : {
               "index" : "test_source", 
               "alias" : "test" 
           } 
       },
       {
         "add": {
           "index": "test_new",
           "alias": "test"
         }
       }
     ]
   }
   '
   

5. 删除旧索引 test_source

   curl -X DELETE "http://192.168.1.101:9200/test_source?pretty"