字段常用属性设置

1.index是否可以检索

index 字段是否可以被检索，取值true/false，默认true。

#创建索引
PUT user_test_001
{
	"mappings":{
		"properties":{
			"id":{
				"type":"integer",
				"index":false
			},
			"name":{
				"type":"text",
				"index":true
			}
		}
	}
}
#插入数据
PUT user_test_001/_create/1
{
	"id":"1001",
	"name":"william"
}
#检索
GET user_test_001/_search
{
  "query": {
    "match": {
      "id": "1001"
    }
  }
}
#搜索提示："failed to create query: Cannot search on field [id] since it is not #indexed."
GET user_test_001/_search
{
  "query": {
    "match": {
      "name": "william"
    }
  }
}

2.store 是否存储

es默认原始数据存储在_source里，其实也可以在lucene里面存储一份，通过此关键字控制取值，默认不存储，作用在字段上，很精细化。原始数据_source被禁用，也需要修改原始数据。当数据量大时，才可能用上该属性。

#创建索引
PUT user_test_001
{
	"mappings":{
		"properties":{
			"userId":{
				"type":"integer",
				"store":true
			},
			"name":{
				"type":"text",
				"store": true
			},
			"address":{
				"type":"text",
				"store": false
			}
		}
	}
}
#插入数据
PUT user_test_001/_create/1
{
	"userId":"1001",
	"name":"william",
	"address":"深圳南山区"
}


#检索
GET user_test_001/_search
{
  "stored_fields": ["userId","name"], 
  "query": {
    "match_all": {}
  }
}

3.enabled 能否启用

设置字段是否需要被检索，作用在object，举例，先设置enabled: true，看看mapping

# 设置mappings
PUT user_test_001
{
	"mappings":{
		"_source":{
			"enabled":false
		}
		"properties":{
			"id":{
				"type":"integer",
				"index":false
			},
			"name":{
				"type":"text",
				"store": true
			},
			"job":{
				"type":"object",
				"enabled":true
			}
		}
	}
}
#查看索引

接下来enabled设置为false

# 设置mappings
PUT user_test_001
{
	"mappings":{
		"_source":{
			"enabled":false
		}
		"properties":{
			"id":{
				"type":"integer",
				"index":false
			},
			"name":{
				"type":"text",
				"store": true
			},
			"job":{
				"type":"object",
				"enabled":false
			}
		}
	}
}

#查看mapping.  发现字段类型为object类型的job的变化。
通过这种方式，可以扩展字段个数。

# 插入数据
PUT user_test_001/_create/1
{
	"id":"1001",
	"name":"william",
	"job":{
		"company":"apple",
		"department":"software",
		"post":"java development"
	}
}

# 检索
GET user_test_01/_search
{
	"query":{
		"match":{
			"id":"1"
		}
	}
}

4.doc_value 能否聚合排序

列式数据库存储。es数据存储，原始数据一份

# 设置mappings
PUT user_test_001
{
	"mappings":{
		"_source":{
			"enabled":true
		},
		"properties":{
			"userId":{
				"type":"integer",
				"doc_values":false
			},
			"name":{
				"type":"text",
				"doc_values": true
			},
			"age":{
				"type":"integer",
				"doc_values":true
			},
			"hobby":{
				"type":"text",
				"doc_values":false
			}
		}
	}
}


# 插入数据
PUT user_test_001/_create/1
{
	"userId":"1001",
	"name":"william",
	"age":18,
	"hobby":"唱歌、跳舞"
}

PUT user_test_001/_create/2
{
	"userId":"1001",
	"name":"john",
	"age":22,
	"hobby":"唱歌"
}
#排序
GET user_test_001/_search
{
	"query":{
		"match_all":{}
	},
	"sort":[
		{
			"userId":{
				"order":"desc"
			}
		}
	]
}
#报错不能根据userId进行排序，可以试试根据age
#聚合
GET user_test_001/_search
{
	"size":0,
	"aggs":{
		"age_avg":{
			"avg":{
				"field":"age"
			}
		}
	}
}

5.null_value 空值设置

对于聚合功能，需要设置默认值，若不设置，值为空，则会出现异常情况。与数据库不同的是，es并不会存储设置的默认空值，仅仅用来做索引检索。

PUT user_test_001
{
	"mappings":{
	   "_source":{
      "enabled":true
     },
		"properties":{
			"userId":{
				"type":"integer"
			},
			"name":{
				"type":"text"
			},
			"income":{
				"type":"integer",
				"null_value":0
			}
		}
	}
}

PUT user_test_001/_doc/1
{
	"userId":"1001",
	"name":"william"
}

GET user_test_001/_search
{
  "size":0,
  "aggs":{
    "sum_income":{
      "sum":{
        "field": "income"
      }
    }
  }
  
}

6.properties 子对象字段约束

PUT user_test_001
{
  "mappings": {
    "_source": {
      "enabled": true
    },
    "properties": {
      "userId": {
        "type": "integer"
      },
      "name": {
        "type": "text"
      },
      "work": {
        "type": "object",
        "properties": {
          "company": {
            "properties": {
              "companyName": {
                "type": "keyword"
              },
              "position": {
                "type": "keyword"
              }
            }
          },
          "city": {
            "type":"object",
            "enabled":false
          }
        }
      }
    }
  }
}

7.dynamic 子对象动态扩展

是否容许对象下面的属性自由扩展，严格限制子对象下面的字段行为。取值：true/false/strict，默认true

PUT user_test_001
{
  "mappings": {
    "_source": {
      "enabled": true
    },
    "properties": {
      "userId": {
        "type": "integer"
      },
      "name": {
        "type": "text"
      },
      "work": {
        "dynamic": "strict",
        "properties": {
          "company": {
            "properties": {
              "companyName": {
                "type": "keyword"
              },
              "position": {
                "type": "keyword"
              }
            }
          },
          "city": {
            "type":"object",
            "enabled":false
          }
        }
      }
    }
  }
}

PUT user_test_001/_doc/1
{
	"userId":"1001",
	"name":"william",
	"work":{
	  "company":{
	    "companyName":"tencent",
	    "position":"java"
	  },
	  "city":{
	    "area":"南山区",
	    "street":"粤海街道"
	  }
	}
}