使用SQL查询ES数据
- 32 进阶:使用SQL查询ES数据
- 环境准备
- 利用脚本导入测试数据
- SQL学习
- 基本查询
- 排序查询
- 过滤查询
- 范围查询
- 分组查询(group)
- 分组过滤查询(group+having)
- 聚合函数统计
- limit查询
- 分页查询
32 进阶:使用SQL查询ES数据
环境准备
需要首先安装ES8.x 和 Kibana8.x,自行安装
利用脚本导入测试数据
这里使用的是python脚本,直接运行即可
Elasticsearch([“https://elastic:=k8dCIlKnwM=mSXHVGO8@192.168.64.7:9200”], verify_certs=False)
这一步部分填写你自己的信息即可
from elasticsearch import Elasticsearch
from faker import Faker
import ssl
import random
es = Elasticsearch(["https://elastic:=k8dCIlKnwM=mSXHVGO8@192.168.64.7:9200"], verify_certs=False)
# 连接到 Elasticsearch 实例# 创建一个 Faker 实例,用于生成有意义的假数据
fake = Faker()# 创建索引(类似于数据库中的表)
index_name = 'test_sql_query4'
es.indices.create(index=index_name, ignore=400)# 插入 2000 条有意义的数据
for i in range(2000):doc = {'name': random.choice(['秦', '楚', '齐', '燕', '韩', '魏', '赵']),'age': fake.random_int(min=18, max=99, step=1),'city': fake.city(),'occupation': fake.job(),'salary': fake.random_int(min=30000, max=100000, step=1000),'timestamp': fake.date_time_this_decade().strftime("%Y-%m-%d")}es.index(index=index_name, body=doc)print("数据插入完成。")
如何按照上面的步骤,安装成功后就可以学习今天的内容了
SQL学习
# 解析SQL
POST /_sql/translate
{"query": """SELECT * FROM "test_sql_query4" order by age LIMIT 10"""
}
基本查询
POST /_sql?format=txt
{"query": """SELECT * FROM "test_sql_query4""""
}
排序查询
POST /_sql?format=txt
{"query": """SELECT * FROM "test_sql_query4" order by age desc"""
}
过滤查询
POST /_sql?format=txt
{"query": """SELECT * FROM "test_sql_query4" where name='秦' order by age desc"""
}POST /_sql?format=txt
{"query": """SELECT * FROM "test_sql_query4" where name in ('秦','赵') order by age desc"""
}
范围查询
POST /_sql?format=txt
{"query": """SELECT * FROM "test_sql_query4" where age<50 and age>30 order by age desc"""
}
分组查询(group)
POST /_sql?format=txt
{"query": """SELECT name,count(1) FROM "test_sql_query4" group by name"""
}
分组过滤查询(group+having)
POST /_sql?format=txt
{"query": """SELECT name,count(1) FROM "test_sql_query4" group by name having count(1)>300"""
}
聚合函数统计
POST /_sql?format=txt
{"query": """SELECT count(name),max(age),min(age),sum(salary) FROM "test_sql_query4""""
}
limit查询
POST /_sql?format=txt
{"query": """SELECT * FROM "test_sql_query4" order by age limit 10"""
}
分页查询
POST /_sql?format=json
{"query": """SELECT * FROM "test_sql_query4" order by age""","fetch_size":2
}
POST /_sql?format=json
{"cursor": "从前面一次查询中获得"
}