这是另一个解决方案，现在使用匹配表达式

源过滤允许控制每次命中_source字段返回的方式。

使用Elastiscsearch 5.5版进行测试

关键字includes定义了具体字段。

GET /my_indice/my_indice_type/_search
{
  "_source": {
    "includes": [
      "my_especific_field"
    ]
  },
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "_id": "%my_id_here_without_percent%"
          }
        }
      ]
    }
  }
}

是的，使用一个更好的选择源过滤器。如果你使用JSON进行搜索，它会是这样的:

{
    "_source": ["user", "message", ...],
    "query": ...,
    "size": ...
}

在ES 2.4和更早的版本中，你也可以在搜索API中使用fields选项:

{
    "fields": ["user", "message", ...],
    "query": ...,
    "size": ...
}

这在ES 5+中已弃用。而且源过滤器更强大!

如果你懂sql，请写一个查询来获取代码的值，例如sql查询等价和elasticsearch查询

POST /_sql/translate
{
  
  "query": "select name,surname from users"
}

结果是，请仔细查看includes键

{
  "size" : 1000,
  "_source" : {
    "includes" : [
      "name",
      "surname"
    ],
    "excludes" : [ ]
  },
  "sort" : [
    {
      "_doc" : {
        "order" : "asc"
      }
    }
  ]
}

REST API GET请求可以使用'_source'参数进行。

示例请求

http://localhost:9200/opt_pr/_search?q=SYMBOL:ITC AND OPTION_TYPE=CE AND TRADE_DATE=2017-02-10 AND EXPIRY_DATE=2017-02-23&_source=STRIKE_PRICE

响应

{
"took": 59,
"timed_out": false,
"_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
},
"hits": {
    "total": 104,
    "max_score": 7.3908954,
    "hits": [
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uLc",
            "_score": 7.3908954,
            "_source": {
                "STRIKE_PRICE": 160
            }
        },
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uLh",
            "_score": 7.3908954,
            "_source": {
                "STRIKE_PRICE": 185
            }
        },
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uLi",
            "_score": 7.3908954,
            "_source": {
                "STRIKE_PRICE": 190
            }
        },
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uLm",
            "_score": 7.3908954,
            "_source": {
                "STRIKE_PRICE": 210
            }
        },
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uLp",
            "_score": 7.3908954,
            "_source": {
                "STRIKE_PRICE": 225
            }
        },
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uLr",
            "_score": 7.3908954,
            "_source": {
                "STRIKE_PRICE": 235
            }
        },
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uLw",
            "_score": 7.3908954,
            "_source": {
                "STRIKE_PRICE": 260
            }
        },
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uL5",
            "_score": 7.3908954,
            "_source": {
                "STRIKE_PRICE": 305
            }
        },
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uLd",
            "_score": 7.381078,
            "_source": {
                "STRIKE_PRICE": 165
            }
        },
        {
            "_index": "opt_pr",
            "_type": "opt_pr_r",
            "_id": "AV3K4QTgNHl15Mv30uLy",
            "_score": 7.381078,
            "_source": {
                "STRIKE_PRICE": 270
            }
        }
    ]
}

}

例如，你有一个有三个字段的doc:

PUT movie/_doc/1
{
  "name":"The Lion King",
  "language":"English",
  "score":"9.3"
}

如果你想返回名字和分数，你可以使用下面的命令:

GET movie/_doc/1?_source_includes=name,score

如果你想获得一些匹配模式的字段:

GET movie/_doc/1?_source_includes=*re

可能会排除一些字段:

GET movie/_doc/1?_source_excludes=score

是的，通过使用源过滤器你可以做到这一点，这里是文档源过滤器

示例请求

POST index_name/_search
 {
   "_source":["field1","filed2".....] 
 }

输出将是

{
  "took": 57,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "skipped": 0,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 1,
    "hits": [
      {
        "_index": "index_name",
        "_type": "index1",
        "_id": "1",
        "_score": 1,
        "_source": {
          "field1": "a",
          "field2": "b"
        },
        {
          "field1": "c",
          "field2": "d"
        },....
      }
    ]
  }
}