一、结构化数据
1.1 结构化搜索（Structured search）是指对结构化数据的搜索
- 日期，布尔类型和数字都是结构化的
1.2 文本也可以是结构化的
- 如彩色笔可以有离散的颜色集合：红（red） 绿（green） 蓝（blue）
- 一个博客可能被标记为标签，例如，分布式（distributed）和搜索（search）
- 电商网站上的商品都有UPCS（通用商品码Universal Product Codes）或其他的唯一标识，他们都需要遵从严格规定的、结构化的格式
二、ES中的结构化搜索
2.1 布尔，时间，日期和数字这类结构化数据：有精确的格式，我们可以对这些格式进行逻辑操作。
- 包括比较数字或时间的范围，或判定两个值的大小
2.2 结构化的文本可以做精确匹配或者部分匹配
- Term 查询 / Prefix 前缀查询
2.3 结构化的结果只有“是”或“否”两个值
- 根据场景需要，可以决定结构化搜索是否需要打分
三、布尔值
image.png
对布尔值，通过constant score 转成 filtering，没有算分
image.png
四、数字
- 数字类型 Term 单个值
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"term": {
"price": 30
}
}
}
- 数字类型 Terms 多个值 类比 SQL中的in函数
POST products/_search
{
"query": {
"constant_score": {
"filter": {
"terms": {
"price": [
"20",
"30"
]
}
}
}
}
}
-
数字范围 20 <= price <= 30
image.png
五、日期 Range 范围
image.png
六、处理空值 exists
image.png
七、查询多个精确值 terms
image.png
- 匹配一个精确值
#数字类型 terms
POST products/_search
{
"query": {
"constant_score": {
"filter": {
"terms": {
"price": [
"20"
]
}
}
}
}
}
八、Term查询是包含，不是完全相等。针对多字段查询要尤其注意
image.png
#结构化搜索，精确匹配
DELETE products
POST /products/_bulk
{ "index": { "_id": 1 }}
{ "price" : 10,"avaliable":true,"date":"2018-01-01", "productID" : "XHDK-A-1293-#fJ3" }
{ "index": { "_id": 2 }}
{ "price" : 20,"avaliable":true,"date":"2019-01-01", "productID" : "KDKE-B-9947-#kL5" }
{ "index": { "_id": 3 }}
{ "price" : 30,"avaliable":true, "productID" : "JODL-X-1937-#pV7" }
{ "index": { "_id": 4 }}
{ "price" : 30,"avaliable":false, "productID" : "QQPX-R-3956-#aD8" }
GET products/_mapping
#对布尔值 match 查询，有算分
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"term": {
"avaliable": true
}
}
}
#对布尔值，通过constant score 转成 filtering，没有算分
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"constant_score": {
"filter": {
"term": {
"avaliable": true
}
}
}
}
}
#数字类型 Term
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"term": {
"price": 30
}
}
}
#数字类型 terms
POST products/_search
{
"query": {
"constant_score": {
"filter": {
"terms": {
"price": [
"20",
"30"
]
}
}
}
}
}
#数字 Range 查询
GET products/_search
{
"query" : {
"constant_score" : {
"filter" : {
"range" : {
"price" : {
"gte" : 20,
"lte" : 30
}
}
}
}
}
}
# 日期 range
POST products/_search
{
"query" : {
"constant_score" : {
"filter" : {
"range" : {
"date" : {
"gte" : "now-1y"
}
}
}
}
}
}
#exists查询
POST products/_search
{
"query": {
"constant_score": {
"filter": {
"exists": {
"field": "date"
}
}
}
}
}
#处理多值字段
POST /movies/_bulk
{ "index": { "_id": 1 }}
{ "title" : "Father of the Bridge Part II","year":1995, "genre":"Comedy"}
{ "index": { "_id": 2 }}
{ "title" : "Dave","year":1993,"genre":["Comedy","Romance"] }
#处理多值字段，term 查询是包含，而不是等于
POST movies/_search
{
"query": {
"constant_score": {
"filter": {
"term": {
"genre.keyword": "Comedy"
}
}
}
}
}
#字符类型 terms
POST products/_search
{
"query": {
"constant_score": {
"filter": {
"terms": {
"productID.keyword": [
"QQPX-R-3956-#aD8",
"JODL-X-1937-#pV7"
]
}
}
}
}
}
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"match": {
"price": 30
}
}
}
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"term": {
"date": "2019-01-01"
}
}
}
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"match": {
"date": "2019-01-01"
}
}
}
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"constant_score": {
"filter": {
"term": {
"productID.keyword": "XHDK-A-1293-#fJ3"
}
}
}
}
}
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"term": {
"productID.keyword": "XHDK-A-1293-#fJ3"
}
}
}
#对布尔数值
POST products/_search
{
"query": {
"constant_score": {
"filter": {
"term": {
"avaliable": "false"
}
}
}
}
}
POST products/_search
{
"query": {
"term": {
"avaliable": {
"value": "false"
}
}
}
}
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"term": {
"price": {
"value": "20"
}
}
}
}
POST products/_search
{
"profile": "true",
"explain": true,
"query": {
"match": {
"price": "20"
}
}
}
}
POST products/_search
{
"query": {
"constant_score": {
"filter": {
"bool": {
"must_not": {
"exists": {
"field": "date"
}
}
}
}
}
}
}
https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-exists-query.html https://www.elastic.co/guide/en/elasticsearch/reference/7.1/term-level-queries.html