使用SQL查询ES数据
- [32 进阶:使用SQL查询ES数据](#32 进阶:使用SQL查询ES数据)
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"
}