https://leetcode.cn/studyplan/sql-premium-50/
一、查询
1821. 寻找今年具有正收入的客户
selectcustomer_id
from Customers
where year = 2021
group by customer_id
having sum(revenue) > 0
183. 从不订购的客户
select c.name as Customers
from Customers c
left join Orders o on c.id = o.customerId
where o.id is null
1873. 计算特殊奖金
selectemployee_id,case when mod(employee_id,2) = 1 and substr(name,1,1) != 'M' then salaryelse 0end as bonus
from Employees
order by employee_id
1398. 购买了产品 A 和产品 B 却没有购买产品 C 的顾客
selectcustomer_id,customer_name
from Customers
where customer_id in (selectcustomer_idfrom Orderswhere product_name in ('A','B')and customer_id not in (select customer_id from Orders where product_name = 'C')group by customer_idhaving count(distinct product_name) = 2
)
order by customer_id
1112. 每位学生的最高成绩
select student_id,course_id,grade
from (
selecte.*,rank() over(partition by student_id order by grade desc,course_id) as rk
from Enrollments e
) where rk = 1
order by student_id二、连接
175. 组合两个表
selectfirstName,lastName,city,state
from Person p
left join Address a on p.PersonId = a.PersonId
1607. 没有卖出的卖家
select seller_name
from Seller
where seller_id not in (
select seller_id
from Orders
where to_char(sale_date,'yyyy') = '2020'
)order by seller_name1407. 排名靠前的旅行者
selectname,nvl( sum(distance) ,0) as travelled_distance
from Users u
left join Rides r on u.id = r.user_id
group by name,u.id
order by travelled_distance desc,name
607. 销售员
selectname
from SalesPerson
where sales_id not in (selectsales_idfrom Orders oleft join Company c on o.com_id = c.com_idwhere c.name = 'RED'
)
1440. 计算布尔表达式的值
select e.*,case when operator = '>' and v1.value > v2.value then 'true'when operator = '<' and v1.value < v2.value then 'true'when operator = '=' and v1.value = v2.value then 'true'else 'false'end as valuefrom Expressions e
join Variables v1 on e.left_operand = v1.name
join Variables v2 on e.right_operand = v2.name
1212. 查询球队积分
with t1 as (selectm.*,case when host_goals > guest_goals then 3when host_goals = guest_goals then 1else 0 end as host_p,case when host_goals < guest_goals then 3when host_goals = guest_goals then 1else 0 end as gust_pfrom Matches m
)selectt.team_id ,team_name,nvl(sum_p,0) as num_points
from Teams t
left join (selectteam_id,sum(p) as sum_pfrom (selecthost_team as team_id,host_p as p from t1union all selectguest_team as team_id,gust_p as p from t1) group by team_id
) a on t.team_id = a.team_id
order by num_points desc,team_id
三、聚合函数
1890. 2020年最后一次登录
select user_id,last_stamp
from (select user_id,time_stamp as last_stamp ,row_number() over(partition by user_id order by time_stamp desc) as rk from Loginswhere to_char(time_stamp,'yyyy') = '2020'
) where rk = 1
511. 游戏玩法分析 I
selectplayer_id,to_char( min(event_date) ,'yyyy-mm-dd') as first_login
from Activity
group by player_id
1571. 仓库经理
selectname as warehouse_name,nvl(sum(units * Width * Length * Height),0) as volume
from Warehouse w
left join Products p on w.product_id = p.product_id
group by name
586. 订单最多的客户
select * from (selectcustomer_numberfrom Ordersgroup by customer_numberorder by count(order_number) desc
) where rownum <= 1
1741. 查找每个员工花费的总时间
selectto_char(event_day,'yyyy-mm-dd') as day,emp_id,sum( out_time - in_time ) as total_time
from Employees
group by emp_id,event_day
1173. 即时食物配送 I
selectround(count(case when order_date = customer_pref_delivery_date then delivery_id end)*100/ count( delivery_id ),2) as immediate_percentage
from Delivery1445. 苹果和桔子
selectto_char(sale_date) as sale_date,sum(case when fruit = 'apples' then sold_num end) - sum(case when fruit = 'oranges' then sold_num end)as diff
from Sales
group by to_char(sale_date)
order by sale_date1699. 两人之间的通话次数
with t1 as (selectfrom_id as p1,to_id as p2,durationfrom Callsunion allselectto_id as p1,from_id as p2,durationfrom Calls
)selectp1 as person1,p2 as person2,count(*) as call_count,sum(duration) as total_duration
from t1
where p1 < p2
group by p1,p2 四、排序和分组
1587. 银行账户概要 II
selectu.name,sum(amount) as balance
from Users u
left join Transactions t on u.account = t.account
group by u.account,u.name
having sum(amount) > 10000
182. 查找重复的电子邮箱
selectemail
from Person
group by email
having count(id) > 1
1050. 合作过至少三次的演员和导演
selectactor_id,director_id
from ActorDirector
group by actor_id,director_id
having count(*) >= 3
1511. 消费者下单频率
select distinct customer_id,name from (selectc.customer_id,c.name, count(to_char(order_date,'yyyy-mm') ) over(partition by c.customer_id) as monfrom Orders o left join Product p on o.product_id = p.product_idleft join Customers c on o.customer_id = c.customer_idwhere to_char(order_date,'yyyy-mm') in ('2020-06','2020-07')group by c.customer_id,c.name,to_char(order_date,'yyyy-mm')having sum(price * quantity) >= 100
) where mon > 11495. 上月播放的儿童适宜电影
selectdistinct title
from TVProgram t
join Content c on t.content_id = c.content_id
where Kids_content = 'Y'
and to_char(program_date,'yyyy-mm') = '2020-06'
and content_type = 'Movies'
1501. 可以放心投资的国家
with t1 as (select caller_id as c1,callee_id as c2 ,duration from Callsunion all select callee_id as c1,caller_id as c2 ,duration from Calls
)select name as country from (selectc.name,avg(duration) as avg_durationfrom t1 join Person p on p.id = t1.c1 join Country c on substr(p.phone_number,1,3) = c.country_codegroup by c.name
) where avg_duration > (select avg(duration) from Calls)
五、高级查询和连接
603. 连续空余座位
select seat_id from (select seat_id,count(seat_id) over(partition by gap) as cntfrom (selectseat_id,seat_id - rank() over(order by seat_id) as gapfrom Cinemawhere free = 1)
) where cnt > 1
order by seat_id
1795. 每个产品在不同商店的价格
selectproduct_id , store , price
from Products
unpivot(price for store in (store1 as 'store1',store2 as 'store2',store3 as 'store3')
)
613. 直线上的最近距离
selectmin( abs(x - lag_x) ) as shortest
from (
selectx,lag(x) over(order by x) as lag_x
from Point
)
1965. 丢失信息的雇员
selectnvl(e.employee_id,s.employee_id) as employee_id
from Employees e
full join Salaries s on e.employee_id = s.employee_id
where e.employee_id is null or s.employee_id is null
order by employee_id1264. 页面推荐
with t1 as (select user1_id as u1 ,user2_id as u2 from Friendship union all select user2_id as u1 ,user1_id as u2 from Friendship
)selectdistinct page_id as recommended_page
from Likes l
join t1 on l.user_id = t1.u2
and t1.u1 = 1
and page_id not in (select page_id from Likes where user_id = 1)
608. 树节点
selectid,case when p_id is null then 'Root'when id not in (select p_id from tree where p_id is not null) then 'Leaf'else 'Inner'end as type
from Tree
534. 游戏玩法分析 III
selectplayer_id,to_char(event_date,'yyyy-mm-dd') as event_date,sum(games_played) over(partition by player_id order by event_daterows between unbounded preceding and current row ) as games_played_so_far
from Activity
1783. 大满贯数量
with t1 as (select*from Championshipsunpivot(cp for game in (Wimbledon as 'Wimbledon',Fr_open as 'Fr_open',US_open as 'US_open',Au_open as 'Au_open'))
) selectp.player_id,player_name,count(*) as grand_slams_count
from t1
join Players p on p.player_id = t1.cp
group by p.player_id,player_name
1747. 应该被禁止的 Leetflex 账户
selectdistinct l1.account_id
from LogInfo l1 join LogInfo l2 on l1.account_id = l2.account_id
and l1.ip_address != l2.ip_address
and l1.login between l2.login and l2.logout512. 游戏玩法分析 II
select player_id,device_id
from (
selectplayer_id,device_id,rank() over(partition by player_id order by event_date) as rk
from Activity
) where rk =1 184. 部门工资最高的员工
select Department,Employee,Salary
from (
selecte.name as EMPLOYEE,e.salary,d.name as Department,rank() over(partition by d.name order by salary desc) as rk
from Employee e
join Department d on e.departmentId = d.id
) where rk = 1
1549. 每件商品的最新订单
select product_name,product_id,order_id,order_date
from (selectproduct_name,o.product_id,order_id,to_char(order_date,'yyyy-mm-dd') as order_date,rank() over (partition by o.product_id order by order_date desc) as rk from Orders o join Products p on o.product_id = p.product_id
) where rk = 1
order by product_name,product_id,order_id
1532. 最近的三笔订单
selectcustomer_name,customer_id,order_id,order_date
from (selectname as customer_name,o.customer_id,order_id,to_char(order_date,'yyyy-mm-dd') as order_date,row_number() over(partition by o.customer_id order by order_date desc) as rk from Orders o join Customers c on o.customer_id = c.customer_id
)where rk <= 3
order by customer_name,customer_id,order_date desc
1831. 每天的最大交易
selecttransaction_id
from (selecttransaction_id,rank() over(partition by trunc(day) order by amount desc ) as rk from Transactions
) where rk = 1
order by transaction_id
六、子查询
1350. 院系无效的学生
selectid,name
from Students
where department_id not in (select id from Departments
)
1303. 求团队人数
selectemployee_id,count(employee_id) over(partition by team_id) as team_size
from Employee
七、窗口函数和公共表表达式CTE
1077. 项目员工 III
select project_id,employee_id
from (selectproject_id,p.employee_id,rank() over(partition by project_id order by experience_years desc) as rk from Project p left join Employee e on e.employee_id = p.employee_id
)where rk = 1
1285. 找到连续区间的开始和结束数字
selectmin(log_id) as start_id,max(log_id) as end_id
from(selectlog_id,log_id - row_number() over(order by log_id) as gapfrom Logs l
)group by gap
order by start_id
1596. 每位顾客最经常订购的商品
select a.customer_id,a.product_id,p.product_name
from (selectproduct_id,customer_id,rank() over(partition by customer_id order by count(order_id) desc) as rk from Ordersgroup by product_id,customer_id
) a
join Products p on a.product_id = p.product_id and a.rk = 1
1709. 访问日期之间最大的空档期
select user_id,max(gap) as biggest_window
from (selectuser_id,visit_date,lead(visit_date,1,to_date('2021-1-1','yyyy-mm-dd')) over(partition by user_id order by visit_date) - visit_date as gapfrom UserVisits
)group by user_id
1270. 向公司 CEO 汇报工作的所有人
select distinct employee_id
from Employees
where employee_id != 1
start with manager_id = 1
connect by nocycle prior employee_id = manager_id
