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题解 | #检索每个顾客的名称和所有的订单号（一）#

select cust_name, order_num from Customers c inner join Orders o on c.cust_id=o.cust_id group by cust_name, order_num # 由于是顾客号与订单号一一对应，故该分组也可以不加 ord...

2023-12-21

0 130

题解 | 使用连接和分组查询

/*使用连接+分组查询*/ select cust_name, sum(item_price*quantity) total_price from OrderItems oi join Orders o on oi.order_num=o.order_num join Customers c on ...

2023-12-21

0 182

题解 | 哪些订单购买了BR01 的产品

# 简单等连接查询，用where包装连接条件和查询条件 select cust_id, order_date from OrderItems oi, Orders o where oi.order_num=o.order_num and prod_id='BR01' order by order_d...

2023-12-21

0 173

题解 | 使用模糊查询筛选日期

select * from Orders where order_date like '2020-01%' order by order_date;

2023-12-21

0 182

题解 | 字符串截取、拼接、大写

select cust_id, cust_name, upper(concat(substring(cust_contact,1,2), substring(cust_city,1,3))) as user_login from Customers;

2023-12-21

0 179

题解 | #返回顾客名称和相关订单号以及每个订单的总价#

# 题目未说明，故未考虑一个顾客有多个订单的情况 select c.cust_name, o.order_num, oi.quantity*oi.item_price OrderTotal from Customers c join Orders o on c.cust_id=o.cust_id j...

2023-12-20

0 147

题解 | #返回顾客名称和相关订单号#

# sql92语法的内连接使用 select cust_name, order_num from Customers c,Orders o where c.cust_id=o.cust_id order by cust_name;

2023-12-20

0 151

题解 | 放在select后面的子查询使用

select prod_name, ( select sum(quantity) from OrderItems where prod_id=p.prod_id ) quant_sold from Products p;

2023-12-20

0 177

题解 | #返回购买某产品的所有顾客的电子邮件-子查询#

# 查询购买prod_id为BR01的产品的所有顾客号 select cust_id from OrderItems oi join Orders o on oi.order_num=o.order_num where prod_id='BR01' # 查询购买prod_id为BR01的产品的所有顾...

2023-12-20

0 170

题解 | #计算总和#

select order_num, sum(item_price*quantity) total_price from OrderItems group by order_num having sum(item_price*quantity)>=1000 order by order_num ...

2023-12-20

0 172