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题解 | #近一个月发布的视频中热度最高的top3视频#

# 连接表，求得所需要的字段 # 计算热度相关的因素 # 找出近一个月热度最高的top 3 with month_time as ( select uvl.*, vi.duration, vi.release_time, c...

2024-04-29

1 209

题解 | #插入记录（一）#

insert into exam_record(uid, exam_id, start_time, submit_time, score) values (1001, 9001, '2021-09-01 22:11:12', '2021-09-01 22:11:12' + interval 50 m...

2024-02-05

2 170

题解 | #返回产品名称和每一项产品的总订单数#

select p.prod_name, count(o.order_num) orders from Products p left join OrderItems o on p.prod_id = o.prod_id group by p.prod_name order by p.prod_n...

2024-01-24

1 158

题解 | #运动会各项目报名透视表#

import pandas as pd f1 = pd.read_csv('items.csv') f2 = pd.read_csv('signup.csv') f = pd.merge(f1, f2, on = 'item_id') print( pd.pivot_table(f, in...

2024-01-18

4 281

题解 | #返回产品名称和与之相关的订单号#

#该题要求使用outer join,但是由于mysql不支持outer join,所以只能使用left join +right join实现全联结 (select p.prod_name, oi.order_num from Products p left join OrderItems oi on...

2024-01-17

1 205

题解 | #确定最佳顾客的另一种方式（二）#

select c.cust_name, A.total_price from Customers c inner join (select o.cust_id, sum(oi.item_price*quantity*1.000) total_price from OrderItems oi inn...

2024-01-17

2 187

题解 | 返回prod_id为BR01的所有顾客的电子邮件

select c.cust_email from Customers c where c.cust_id in ( select o.cust_id from Orders o left join OrderItems oi on oi.order_num = o.o...

2024-01-17

1 200

题解 | #返回顾客名称和相关订单号以及每个订单的总价#

select A.cust_name, A.order_num, oi.quantity*oi.item_price OrderTotal from (select c.cust_name, o.order_num from Customers c inner join O...

2024-01-17

1 192

题解 | #返回每个顾客不同订单的总金额#

select o.cust_id, ( select sum(q.item_price*q.quantity) from OrderItems q where q.order_num = o.order_num ) total_ord...

2024-01-14

1 200

题解 | #牛客网每日正确与错误的答题次数#

import pandas as pd f = pd.read_csv('nowcoder.csv') f['year-month-day'] = pd.to_datetime(f['date']).dt.date sort = (pd.to_datetime(f['date']).dt.year...

2024-01-14

2 188