# Write your MySQL query statement below
1173. 即时食物配送 I
配送表: Delivery
+-----------------------------+---------+ | Column Name | Type | +-----------------------------+---------+ | delivery_id | int | | customer_id | int | | order_date | date | | customer_pref_delivery_date | date | +-----------------------------+---------+ 在 SQL 中，delivery_id 是表的主键。 该表保存着顾客的食物配送信息，顾客在某个日期下了订单，并指定了一个期望的配送日期（和下单日期相同或者在那之后）。
如果顾客期望的配送日期和下单日期相同，则该订单称为 「即时订单」，否则称为「计划订单」。
查询即时订单所占的百分比， 保留两位小数。
查询结果如下所示。
示例 1:
输入： Delivery 表: +-------------+-------------+------------+-----------------------------+ | delivery_id | customer_id | order_date | customer_pref_delivery_date | +-------------+-------------+------------+-----------------------------+ | 1 | 1 | 2019-08-01 | 2019-08-02 | | 2 | 5 | 2019-08-02 | 2019-08-02 | | 3 | 1 | 2019-08-11 | 2019-08-11 | | 4 | 3 | 2019-08-24 | 2019-08-26 | | 5 | 4 | 2019-08-21 | 2019-08-22 | | 6 | 2 | 2019-08-11 | 2019-08-13 | +-------------+-------------+------------+-----------------------------+ 输出： +----------------------+ | immediate_percentage | +----------------------+ | 33.33 | +----------------------+ 解释：2 和 3 号订单为即时订单，其他的为计划订单。
原站题解
pythondata 解法, 执行用时: 272 ms, 内存消耗: 59.4 MB, 提交时间: 2023-08-09 15:00:21
import pandas as pd
def food_delivery(delivery: pd.DataFrame) -> pd.DataFrame:
# 计算即时订单所占的百分比
immediate_percentage = round((delivery['order_date'] == delivery['customer_pref_delivery_date']).mean() * 100, 2)
return pd.DataFrame({'immediate_percentage': [immediate_percentage]})
mysql 解法, 执行用时: 446 ms, 内存消耗: 0 B, 提交时间: 2023-07-31 09:45:32
# Write your MySQL query statement below
# 0x03 sum
select round (
sum(order_date = customer_pref_delivery_date) /
count(*) * 100,
2
) as immediate_percentage
from Delivery;
mysql 解法, 执行用时: 340 ms, 内存消耗: 0 B, 提交时间: 2023-07-31 09:45:00
# Write your MySQL query statement below
# 0x02 sum 和 case when
select round (
sum(case when order_date = customer_pref_delivery_date then 1 else 0 end) /
count(*) * 100,
2
) as immediate_percentage
from Delivery;
mysql 解法, 执行用时: 526 ms, 内存消耗: 0 B, 提交时间: 2023-07-31 09:44:44
# Write your MySQL query statement below
# 0x01 直接计算
select round (
(select count(*) from Delivery where order_date = customer_pref_delivery_date) /
(select count(*) from Delivery) * 100,
2
) as immediate_percentage;