文档条件查询

在前面我们讲过对文档的查询,但是仅用了id全查的方式, 这样的查询在实践中往往不能够满足多样化的检索需求。根据条件检索是非常必须的。条件查询的URL地址格式为http://127.0.0.1:9200/shopping/_search/q=查询条件.
例如我们希望直接查询品类为床上用品的所有数据. URL地址为:http://127.0.0.1:9200/shopping/_search?q=category:床上用品. 查询的请求方式为GET。发起请求如下图:
 
响应结果:

{
   
     
    "took": 25,
    "timed_out": false,
    "_shards": {
   
     
        "total": 1,
        "successful": 1,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
   
     
        "total": {
   
     
            "value": 2,
            "relation": "eq"
        },
        "max_score": 0.72928625,
        "hits": [
            {
   
     
                "_index": "shopping",
                "_type": "_doc",
                "_id": "1001",
                "_score": 0.72928625,
                "_source": {
   
     
                    "title": "水星家纺被子夏季空调被 夏凉被夏天被子双人夏被被芯学生宿舍被子200*230cm",
                    "category": "床上用品",
                    "image": "https://img11.360buyimg.com/n7/jfs/t1/191056/14/24248/144443/62767f75E23ccafc4/5110691845cfa4cf.jpg",
                    "price": 169.0
                }
            },
            {
   
     
                "_index": "shopping",
                "_type": "_doc",
                "_id": "1002",
                "_score": 0.72928625,
                "_source": {
   
     
                    "title": "水星家纺 60S长绒棉贡缎床上四件套 酒店高档纯棉床单被套枕套 被罩被单1.8米床乔伊斯玫瑰(海蓝色/抗菌)",
                    "category": "床上用品",
                    "image": "https://www.shuixing.com/pc/images/2022/logo_02.png",
                    "price": 899.0
                }
            }
        ]
    }
}

上面的操作很类似关系型数据库根据字段,然后模糊查询的结果,其实用http://127.0.0.1:9200/shopping/_search?q=category:床也能面中上面的数据。

通过请求体传参

上面的例子可以看出,在url地址中发送请求条件格式过于复杂,而且还存在在url地址中传入中文等字符,这样的操作很容易出现乱码等问题导致查询出错。所以我们可以考虑使用请求体传参的方式来规避这些问题,ES的条件查询也是支持这样的操作的。
URL地址就比较固定了,URL地址为:http://127.0.0.1:9200/shopping/_search
请求的body结构如下:

{
   
     
    "query":{
   
     
        "match": {
   
     
            "category":"床上用品"
        }
    }
}

查询条件的最外层为query, 匹配条件的字段为matchmatch下是一个对象,可以天上响应的字段内容信息。
 
响应的内容是:

{
   
     
    "took": 2,
    "timed_out": false,
    "_shards": {
   
     
        "total": 1,
        "successful": 1,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
   
     
        "total": {
   
     
            "value": 2,
            "relation": "eq"
        },
        "max_score": 0.72928625,
        "hits": [
            {
   
     
                "_index": "shopping",
                "_type": "_doc",
                "_id": "1001",
                "_score": 0.72928625,
                "_source": {
   
     
                    "title": "水星家纺被子夏季空调被 夏凉被夏天被子双人夏被被芯学生宿舍被子200*230cm",
                    "category": "床上用品",
                    "image": "https://img11.360buyimg.com/n7/jfs/t1/191056/14/24248/144443/62767f75E23ccafc4/5110691845cfa4cf.jpg",
                    "price": 169.0
                }
            },
            {
   
     
                "_index": "shopping",
                "_type": "_doc",
                "_id": "1002",
                "_score": 0.72928625,
                "_source": {
   
     
                    "title": "水星家纺 60S长绒棉贡缎床上四件套 酒店高档纯棉床单被套枕套 被罩被单1.8米床乔伊斯玫瑰(海蓝色/抗菌)",
                    "category": "床上用品",
                    "image": "https://www.shuixing.com/pc/images/2022/logo_02.png",
                    "price": 899.0
                }
            }
        ]
    }
}

和上面GET请求的条件相同,结果相同。