ElasticSearch 学习笔记：Reindex，

ElasticSearch 学习笔记：Reindex，

1、创建新的索引（Index）：

PUT /<indexName>
{
  "settings": {
    "index": {
      "number_of_shards": 5,
      "number_of_replicas": 1
    }
  }
}

2、导入数据（Reindex）：

POST /_reindex
{
  "source": {
    "index": "<sourceIndexName>",
    "type": "<sourceTypeName>",
    "sort": {
      "<fieldName>": "asc/desc"
    },
    "_source": [
      "<fieldName>",
      "<fieldName>",
      ...
    ]
  },
  "dest": {
    "index": "<destIndexName>"
  }
}

3、批量更新（Update by Query）：

POST /<indexName>/<typeName>/_update_by_query
{
  "query": {
    "match_all": {}
  },
  "script": {
    "inline/source": "ctx._source.<fieldName> = ctx._source.<fieldName> + ''"
  }
}

inline：ES 5.6版本之前；

source：ES 5.6版本及以后

4、新建/删除别名（Alias）：

POST /_aliases
{
  "actions": [
    {
      "add": {
        "index": "<indexName>",
        "alias": "<alias>"
      }
    }
  ]
}

{
  "actions": [
    {
      "remove": {
        "index": "<indexName>",
        "alias": "<alias>"
      }
    }
  ]
}