Elasticsearch文档操作
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