一、Elasticsearch的CURD
1、CURD之Create
PUT lqz/doc/1
{"name":"顾老二","age":30,"from": "gu","desc": "皮肤黑、武器长、性格直","tags": ["黑", "长", "直"]
}
他明处貌似还有俩老婆:
PUT lqz/doc/2
{"name":"大娘子","age":18,"from":"sheng","desc":"肤白貌美,娇憨可爱","tags":["白", "富","美"]
}PUT lqz/doc/3
{"name":"龙套偏房","age":22,"from":"gu","desc":"mmp,没怎么看,不知道怎么形容","tags":["造数据", "真","难"]
}
家里红旗不倒,家外彩旗飘摇:
PUT lqz/doc/4
{"name":"石头","age":29,"from":"gu","desc":"粗中有细,狐假虎威","tags":["粗", "大","猛"]
}PUT lqz/doc/5
{"name":"魏行首","age":25,"from":"广云台","desc":"仿佛兮若轻云之蔽月,飘飘兮若流风之回雪,mmp,最后竟然没有嫁给顾老二!","tags":["闭月","羞花"]
}
注意:当执行PUT
命令时,如果数据不存在,则新增该条数据,如果数据存在则修改该条数据。
咱们通过GET
命令查询一下:
GET lqz/doc/1
结果如下:
{"_index" : "lqz","_type" : "doc","_id" : "1","_version" : 1,"found" : true,"_source" : {"name" : "顾老二","age" : 30,"from" : "gu","desc" : "皮肤黑、武器长、性格直","tags" : ["黑","长","直"]}
}
查询也没啥问题,但是你可能说了,人家老二是黄种人,怎么是黑的呢?好吧咱改改desc
和tags
:
PUT lqz/doc/1
{"desc":"皮肤很黄,武器很长,性格很直","tags":["很黄","很长", "很直"]
}
上例,我们仅修改了desc
和tags
两处,而name
、age
和from
三个属性没有变化,我们可以忽略不写吗?查查看:
GET lqz/doc/1
结果如下:
{"_index" : "lqz","_type" : "doc","_id" : "1","_version" : 3,"found" : true,"_source" : {"desc" : "皮肤很黄,武器很长,性格很直","tags" : ["很黄","很长","很直"]}
}
哎呀,出事故了!修改是修改了,但结果不太理想啊,因为name
、age
和from
属性都没啦!
注意:**PUT
命令,在做修改操作时,如果未指定其他的属性,则按照指定的属性进行修改操作。**也就是如上例所示的那样,我们修改时只修改了desc
和tags
两个属性,其他的属性并没有一起添加进去。
很明显,这是病!dai治!怎么治?上车,咱们继续往下走!
2、CURD之Update
让我们首先恢复一下事故现场:
PUT lqz/doc/1
{"name":"顾老二","age":30,"from": "gu","desc": "皮肤黑、武器长、性格直","tags": ["黑", "长", "直"]
}
我们要将黑修改成黄:
POST lqz/doc/1/_update
{"doc": {"desc": "皮肤很黄,武器很长,性格很直","tags": ["很黄","很长", "很直"]}
}
上例中,我们使用POST
命令,在id
后面跟_update
,要修改的内容放到doc
文档(属性)中即可。
我们再来查询一次:
GET lqz/doc/1
结果如下:
{"_index" : "lqz","_type" : "doc","_id" : "1","_version" : 5,"found" : true,"_source" : {"name" : "顾老二","age" : 30,"from" : "gu","desc" : "皮肤很黄,武器很长,性格很直","tags" : ["很黄","很长","很直"]}
}
结果如上例所示,现在其他的属性没有变化,只有desc
和tags
属性被修改。
注意:POST
命令,这里可用来执行修改操作(还有其他的功能),POST
命令配合_update
完成修改操作,指定修改的内容放到doc
中。
写了这么多,我也发现我上面有讲的不对
的地方——石头不是跟顾老二不清不楚,石头是跟小桃不清不楚!好吧,刚才那个数据是一个错误示范!我们这就把它干掉!
3、CURD之Delete
DELETE lqz/doc/4
很简单,通过DELETE
命令,就可以删除掉那个错误示范了!
删除效果如下:
{"_index" : "lqz","_type" : "doc","_id" : "4","_version" : 4,"result" : "deleted","_shards" : {"total" : 2,"successful" : 1,"failed" : 0},"_seq_no" : 4,"_primary_term" : 1
}
我们再来查询一遍:
GET lqz/doc/4
结果如下:
{"_index" : "lqz","_type" : "doc","_id" : "4","found" : false
}
上例中,found:false
表示查询数据不存在。
4、CURD之Retrieve
我们上面已经不知不觉的使用熟悉这种简单查询方式,通过 GET
命令查询指定文档:
GET lqz/doc/1
结果如下:
{"_index" : "lqz","_type" : "doc","_id" : "1","_version" : 5,"found" : true,"_source" : {"name" : "顾老二","age" : 30,"from" : "gu","desc" : "皮肤很黄,武器很长,性格很直","tags" : ["很黄","很长","很直"]}
}
二、Elasticsearch之查询的两种方式
1、前言
简单的没挑战,来点复杂的,elasticsearch提供两种查询方式:
- 查询字符串(query string),简单查询,就像是像传递URL参数一样去传递查询语句,被称为简单搜索或查询字符串(query string)搜索。
- 另外一种是通过DSL语句来进行查询,被称为DSL查询(Query DSL),DSL是Elasticsearch提供的一种丰富且灵活的查询语言,该语言以json请求体的形式出现,通过restful请求与Elasticsearch进行交互。
2、准备数据
PUT lqz/doc/1
{"name":"顾老二","age":30,"from": "gu","desc": "皮肤黑、武器长、性格直","tags": ["黑", "长", "直"]
}PUT lqz/doc/2
{"name":"大娘子","age":18,"from":"sheng","desc":"肤白貌美,娇憨可爱","tags":["白", "富","美"]
}PUT lqz/doc/3
{"name":"龙套偏房","age":22,"from":"gu","desc":"mmp,没怎么看,不知道怎么形容","tags":["造数据", "真","难"]
}PUT lqz/doc/4
{"name":"石头","age":29,"from":"gu","desc":"粗中有细,狐假虎威","tags":["粗", "大","猛"]
}PUT lqz/doc/5
{"name":"魏行首","age":25,"from":"广云台","desc":"仿佛兮若轻云之蔽月,飘飘兮若流风之回雪,mmp,最后竟然没有嫁给顾老二!","tags":["闭月","羞花"]
}
3、查询字符串
GET lqz/doc/_search?q=from:gu
还是使用GET
命令,通过_serarch
查询,查询条件是什么呢?条件是from
属性是gu
家的人都有哪些。最后,别忘了_search
和from
属性中间的英文分隔符?
结果如下:
{"took" : 1,"timed_out" : false,"_shards" : {"total" : 5,"successful" : 5,"skipped" : 0,"failed" : 0},"hits" : {"total" : 3,"max_score" : 0.6931472,"hits" : [{"_index" : "lqz","_type" : "doc","_id" : "4","_score" : 0.6931472,"_source" : {"name" : "石头","age" : 29,"from" : "gu","desc" : "粗中有细,狐假虎威","tags" : ["粗","大","猛"]}},{"_index" : "lqz","_type" : "doc","_id" : "1","_score" : 0.2876821,"_source" : {"name" : "顾老二","age" : 30,"from" : "gu","desc" : "皮肤黑、武器长、性格直","tags" : ["黑","长","直"]}},{"_index" : "lqz","_type" : "doc","_id" : "3","_score" : 0.2876821,"_source" : {"name" : "龙套偏房","age" : 22,"from" : "gu","desc" : "mmp,没怎么看,不知道怎么形容","tags" : ["造数据","真","难"]}}]}
}
我们来重点说下hits
,hits
是返回的结果集——所有from
属性为gu
的结果集。重点中的重点是_score
得分,得分是什么呢?根据算法算出跟查询条件的匹配度,匹配度高得分就高。后面再说这个算法是怎么回事。
4、结构化查询
我们现在使用DSL方式,来完成刚才的查询,查看来自顾家的都有哪些人。
GET lqz/doc/_search
{"query": {"match": {"from": "gu"}}
}
上例,查询条件是一步步构建出来的,将查询条件添加到match
中即可,而match
则是查询所有from
字段的值中含有gu
的结果就会返回。
当然结果没啥变化:
{"took" : 0,"timed_out" : false,"_shards" : {"total" : 5,"successful" : 5,"skipped" : 0,"failed" : 0},"hits" : {"total" : 3,"max_score" : 0.6931472,"hits" : [{"_index" : "lqz","_type" : "doc","_id" : "4","_score" : 0.6931472,"_source" : {"name" : "石头","age" : 29,"from" : "gu","desc" : "粗中有细,狐假虎威","tags" : ["粗","大","猛"]}},{"_index" : "lqz","_type" : "doc","_id" : "1","_score" : 0.2876821,"_source" : {"name" : "顾老二","age" : 30,"from" : "gu","desc" : "皮肤黑、武器长、性格直","tags" : ["黑","长","直"]}},{"_index" : "lqz","_type" : "doc","_id" : "3","_score" : 0.2876821,"_source" : {"name" : "龙套偏房","age" : 22,"from" : "gu","desc" : "mmp,没怎么看,不知道怎么形容","tags" : ["造数据","真","难"]}}]}
}
三、term与match查询
1、match查询
1.1 准备数据
PUT lqz/doc/1
{"name":"顾老二","age":30,"from": "gu","desc": "皮肤黑、武器长、性格直","tags": ["黑", "长", "直"]
}PUT lqz/doc/2
{"name":"大娘子","age":18,"from":"sheng","desc":"肤白貌美,娇憨可爱","tags":["白", "富","美"]
}PUT lqz/doc/3
{"name":"龙套偏房","age":22,"from":"gu","desc":"mmp,没怎么看,不知道怎么形容","tags":["造数据", "真","难"]
}PUT lqz/doc/4
{"name":"石头","age":29,"from":"gu","desc":"粗中有细,狐假虎威","tags":["粗", "大","猛"]
}PUT lqz/doc/5
{"name":"魏行首","age":25,"from":"广云台","desc":"仿佛兮若轻云之蔽月,飘飘兮若流风之回雪,mmp,最后竟然没有嫁给顾老二!","tags":["闭月","羞花"]
}
1.2 match系列之match(按条件查询)
我们查看来自顾家的都有哪些人。
GET lqz/doc/_search
{"query": {"match": {"from": "gu"}}
}
上例,查询条件是一步步构建出来的,将查询条件添加到match
中即可,而match
则是查询所有from
字段的值中含有gu
的结果就会返回。
结果如下:
{"took" : 0,"timed_out" : false,"_shards" : {"total" : 5,"successful" : 5,"skipped" : 0,"failed" : 0},"hits" : {"total" : 3,"max_score" : 0.6931472,"hits" : [{"_index" : "lqz","_type" : "doc","_id" : "4","_score" : 0.6931472,"_source" : {"name" : "石头","age" : 29,"from" : "gu","desc" : "粗中有细,狐假虎