[Oracle]见习BI工程师

打开sqldeveloper
----新建连接----
----新建会话----
----新建会话级临时表----

select * from emp;

----新建中间表 再查找----

with bt as (select emp.*
				   ,rank() over(partition by deptno order by sal desc) rank from emp)
select * from bt where rank<=3; 

----函数-----
–聚合函数–
sum()
avg()
count()
max()
min()
–分析函数–
排名函数
rank() over(partition by 字段 order by 字段)

row_number over(partition by 字段 order by 字段)

dense_rank() over(partition by 字段 order by 字段)

迁移函数
lead() 上移

select ename 姓名
	   ,round((lead(sal,2) over(order by hiredate) -sal)/sal,3)*100||'%' 环比 from emp;

lag() 下移

聚合分析函数
sum(字段) over(order by 字段)

select ename 姓名
	   ,sal 工资
	   ,sum(sal) over(order by hiredate) 累计工资 from emp;

avg(字段) over(order by 字段)
count(字段) over(order by 字段)
max(字段) over(order by 字段)
min(字段) over(order by 字段)

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