Elasticsearch核心知识篇(46)
初识搜索引擎_mapping复杂数据类型以及object类型数据底层结构大揭秘
multivalue field
{ "tags": [ "tag1", "tag2" ]}
- 建立索引时与string是一样的，数据类型不能混
empty field
null，[]，[null]
object field
PUT /company/employee/1
{
"address": {
"country": "china",
"province": "guangdong",
"city": "guangzhou"
},
"name": "jack",
"age": 27,
"join_date": "2017-01-01"
}
GET /company/_mapping/employee
# address：object类型
{
"company": {
"mappings": {
"employee": {
"properties": {
"address": {
"properties": {
"city": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 256
}
}
},
"country": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 256
}
}
},
"province": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 256
}
}
}
}
},
"age": {
"type": "long"
},
"join_date": {
"type": "date"
},
"name": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 256
}
}
}
}
}
}
}
}
- 底层数据存储
{
"address": {
"country": "china",
"province": "guangdong",
"city": "guangzhou"
},
"name": "jack",
"age": 27,
"join_date": "2017-01-01"
}
# 数据底层存储
{
"name": [jack],
"age": [27],
"join_date": [2017-01-01],
"address.country": [china],
"address.province": [guangdong],
"address.city": [guangzhou]
}
# 更加复杂一点数据
{
"authors": [
{ "age": 26, "name": "Jack White"},
{ "age": 55, "name": "Tom Jones"},
{ "age": 39, "name": "Kitty Smith"}
]
}
{
"authors.age": [26, 55, 39],
"authors.name": [jack, white, tom, jones, kitty, smith]
}
Elasticsearch核心知识篇(47)
初识搜索引擎_search api的基础语法介绍
search api的基本语法
# 前面已经使用过了，不在详解
GET /_search
{}
GET /index1,index2/type1,type2/_search
{}
GET /_search
{
"from": 0,
"size": 10
}
http协议中get是否可以带上request body
HTTP协议，一般不允许get请求带上request body，但是因为get更加适合描述查询数据的操作，因此还是这么用了
GET /_search?from=0&size=10
POST /_search
{
"from":0,
"size":10
}
碰巧，很多浏览器，或者是服务器，也都支持GET+request body模式
如果遇到不支持的场景，也可以用POST /_search
Elasticsearch核心知识篇(48)
初识搜索引擎_快速上机动手实战Query DSL搜索语法
一个例子让你明白什么是Query DSL
GET /_search
{
"query": {
"match_all": {}
}
}
Query DSL的基本语法
{
QUERY_NAME: {
ARGUMENT: VALUE,
ARGUMENT: VALUE,...
}
}
{
QUERY_NAME: {
FIELD_NAME: {
ARGUMENT: VALUE,
ARGUMENT: VALUE,...
}
}
}
示例：
GET /waws_index/waws_type/_search
{
"query": {
"match": {
"test_field": "test"
}
}
}
如何组合多个搜索条件
搜索需求：title必须包含elasticsearch，content可以包含elasticsearch也可以不包含，author_id必须不为111
- must : 必须匹配
- should : 可以匹配也可以不进行匹配
- must not : 不能包含
重新生成一批数据
PUT /waws_data/waws_type/1
{
"title": "my hadoop article",
"content": "hadoop is very bad",
"author_id": 111
}
PUT /waws_data/waws_type/2
{
"title": "my elasticsearch article",
"content": "es is very bad",
"author_id": 110
}
PUT /waws_data/waws_type/3
{
"title": "my elasticsearch article",
"content": "es is very goods",
"author_id": 111
}
GET /waws_data/waws_type/_search
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 3,
"max_score": 1,
"hits": [
{
"_index": "waws_data",
"_type": "waws_type",
"_id": "2",
"_score": 1,
"_source": {
"title": "my elasticsearch article",
"content": "es is very goods",
"author_id": 111
}
},
{
"_index": "waws_data",
"_type": "waws_type",
"_id": "1",
"_score": 1,
"_source": {
"title": "my hadoop article",
"content": "hadoop is very bad",
"author_id": 111
}
},
{
"_index": "waws_data",
"_type": "waws_type",
"_id": "3",
"_score": 1,
"_source": {
"title": "my elasticsearch article",
"content": "es is very goods",
"author_id": 111
}
}
]
}
}
满足上面需求的查找语句
GET /waws_data/waws_type/_search
{
"query": {
"bool": {
"must": [
{
"match": {
"title": "elasticsearch"
}
}
],
"should": [
{
"match": {
"content": "elasticsearch"
}
}
],
"must_not": [
{
"match": {
"author_id": 111
}
}
]
}
}
}
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 1,
"max_score": 0.25316024,
"hits": [
{
"_index": "waws_data",
"_type": "waws_type",
"_id": "3",
"_score": 0.25316024,
"_source": {
"title": "my elasticsearch article",
"content": "es is very goods",
"author_id": 110
}
}
]
}
}
- 复杂的查询语句
GET /test_index/_search
{
"query": {
"bool": {
"must": { "match": { "name": "tom" }},
"should": [
{ "match": { "hired": true }},
{ "bool": {
"must": { "match": { "personality": "good" }},
"must_not": { "match": { "rude": true }}
}}
],
"minimum_should_match": 1 # 至少要匹配到一条
}
}
}
