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[Niu Ke brush questions-SQL big factory interview questions] NO4. Travel scene (a taxi)
2022-08-01 21:48:00 【IT Bond】
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文章目录
前言
SQL每个人都要用,但是用来衡量产出的并不是SQL本身,你需要用这个工具,去创造其它的价值.SQL174 2021年国庆在北京接单3次及以上的司机统计信息
建表语句
DROP TABLE IF EXISTS tb_get_car_record,tb_get_car_order;
CREATE TABLE tb_get_car_record (
id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
uid INT NOT NULL COMMENT '用户ID',
city VARCHAR(10) NOT NULL COMMENT '城市',
event_time datetime COMMENT '打车时间',
end_time datetime COMMENT '打车结束时间',
order_id INT COMMENT '订单号'
) CHARACTER SET utf8 COLLATE utf8_bin;
CREATE TABLE tb_get_car_order (
id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
order_id INT NOT NULL COMMENT '订单号',
uid INT NOT NULL COMMENT '用户ID',
driver_id INT NOT NULL COMMENT '司机ID',
order_time datetime COMMENT '接单时间',
start_time datetime COMMENT '开始计费的上车时间',
finish_time datetime COMMENT '订单结束时间',
mileage DOUBLE COMMENT '行驶里程数',
fare DOUBLE COMMENT '费用',
grade TINYINT COMMENT '评分'
) CHARACTER SET utf8 COLLATE utf8_bin;
INSERT INTO tb_get_car_record(uid, city, event_time, end_time, order_id) VALUES
(101, '北京', '2021-10-01 07:00:00', '2021-10-01 07:02:00', null),
(102, '北京', '2021-10-01 09:00:30', '2021-10-01 09:01:00', 9001),
(101, '北京', '2021-10-01 08:28:10', '2021-10-01 08:30:00', 9002),
(103, '北京', '2021-10-02 07:59:00', '2021-10-02 08:01:00', 9003),
(104, '北京', '2021-10-03 07:59:20', '2021-10-03 08:01:00', 9004),
(105, '北京', '2021-10-01 08:00:00', '2021-10-01 08:02:10', 9005),
(106, '北京', '2021-10-01 17:58:00', '2021-10-01 18:01:00', 9006),
(107, '北京', '2021-10-02 11:00:00', '2021-10-02 11:01:00', 9007),
(108, '北京', '2021-10-02 21:00:00', '2021-10-02 21:01:00', 9008) ;
INSERT INTO tb_get_car_order(order_id, uid, driver_id, order_time, start_time, finish_time, mileage, fare, grade) VALUES
(9002, 101, 201, '2021-10-01 08:30:00', null, '2021-10-01 08:31:00', null, null, null),
(9001, 102, 202, '2021-10-01 09:01:00', '2021-10-01 09:06:00', '2021-10-01 09:31:00', 10.0, 41.5, 5),
(9003, 103, 202, '2021-10-02 08:01:00', '2021-10-02 08:15:00', '2021-10-02 08:31:00', 11.0, 41.5, 4),
(9004, 104, 202, '2021-10-03 08:01:00', '2021-10-03 08:13:00', '2021-10-03 08:31:00', 7.5, 22, 4),
(9005, 105, 203, '2021-10-01 08:02:10', '2021-10-01 08:18:00', '2021-10-01 08:31:00', 15.0, 44, 5),
(9006, 106, 203, '2021-10-01 18:01:00', '2021-10-01 18:09:00', '2021-10-01 18:31:00', 8.0, 25, 5),
(9007, 107, 203, '2021-10-02 11:01:00', '2021-10-02 11:07:00', '2021-10-02 11:31:00', 9.9, 30, 5),
(9008, 108, 203, '2021-10-02 21:01:00', '2021-10-02 21:10:00', '2021-10-02 21:31:00', 13.2, 38, 4);
需求
场景逻辑说明：
用户提交打车请求后,在用户打车记录表生成一条打车记录,order_id-The order number is set to null;
当有司机接单时,在打车订单表生成一条订单,填充order_time-The order time and the fields to its left,start_time-The pick-up time and the fields to the right of it are all null,并把order_id-order number andorder_time-接单时间（end_time-打车结束时间）写入打车记录表;若一直无司机接单,超时或中途用户主动取消打车,则记录end_time-打车结束时间.
若乘客上车前,乘客或司机点击取消订单,会将打车订单表对应订单的finish_time-The order completion time is populated with the cancellation time,其余字段设为null.
当司机接上乘客时,填充订单表中该start_time-开始计费的上车时间.
当订单完成时填充订单完成时间、里程数、费用;评分设为null,在用户给司机打1~5星评价后填充.
问题：请统计2021年国庆7天期间在北京市接单至少3次的司机的平均接单数和平均兼职收入（暂不考虑平台佣金,直接计算完成的订单费用总额）,结果保留3位小数.
答案
SELECT "北京" as city, ROUND(AVG(order_num), 3) as avg_order_num,
ROUND(AVG(income), 3) as avg_income
FROM (
SELECT driver_id, COUNT(order_id) as order_num, SUM(fare) as income
FROM tb_get_car_order
JOIN tb_get_car_record USING(order_id)
WHERE city = "北京" and DATE_FORMAT(order_time,"%Y%m%d") BETWEEN '20211001' AND '20211007'
GROUP BY driver_id
HAVING COUNT(order_id) >= 3
) as t_driver_info;
SQL175 有取消订单记录的司机平均评分
建表语句
DROP TABLE IF EXISTS tb_get_car_record,tb_get_car_order;
CREATE TABLE tb_get_car_record (
id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
uid INT NOT NULL COMMENT '用户ID',
city VARCHAR(10) NOT NULL COMMENT '城市',
event_time datetime COMMENT '打车时间',
end_time datetime COMMENT '打车结束时间',
order_id INT COMMENT '订单号'
) CHARACTER SET utf8 COLLATE utf8_bin;
CREATE TABLE tb_get_car_order (
id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
order_id INT NOT NULL COMMENT '订单号',
uid INT NOT NULL COMMENT '用户ID',
driver_id INT NOT NULL COMMENT '司机ID',
order_time datetime COMMENT '接单时间',
start_time datetime COMMENT '开始计费的上车时间',
finish_time datetime COMMENT '订单结束时间',
mileage FLOAT COMMENT '行驶里程数',
fare FLOAT COMMENT '费用',
grade TINYINT COMMENT '评分'
) CHARACTER SET utf8 COLLATE utf8_bin;
INSERT INTO tb_get_car_record(uid, city, event_time, end_time, order_id) VALUES
(101, '北京', '2021-10-01 07:00:00', '2021-10-01 07:02:00', null),
(102, '北京', '2021-10-01 09:00:30', '2021-10-01 09:01:00', 9001),
(101, '北京', '2021-10-01 08:28:10', '2021-10-01 08:30:00', 9002),
(103, '北京', '2021-10-02 07:59:00', '2021-10-02 08:01:00', 9003),
(104, '北京', '2021-10-03 07:59:20', '2021-10-03 08:01:00', 9004),
(105, '北京', '2021-10-01 08:00:00', '2021-10-01 08:02:10', 9005),
(106, '北京', '2021-10-01 17:58:00', '2021-10-01 18:01:00', 9006),
(107, '北京', '2021-10-02 11:00:00', '2021-10-02 11:01:00', 9007),
(108, '北京', '2021-10-02 21:00:00', '2021-10-02 21:01:00', 9008),
(109, '北京', '2021-10-08 18:00:00', '2021-10-08 18:01:00', 9009);
INSERT INTO tb_get_car_order(order_id, uid, driver_id, order_time, start_time, finish_time, mileage, fare, grade) VALUES
(9002, 101, 202, '2021-10-01 08:30:00', null, '2021-10-01 08:31:00', null, null, null),
(9001, 102, 202, '2021-10-01 09:01:00', '2021-10-01 09:06:00', '2021-10-01 09:31:00', 10.0, 41.5, 5),
(9003, 103, 202, '2021-10-02 08:01:00', '2021-10-02 08:15:00', '2021-10-02 08:31:00', 11.0, 41.5, 4),
(9004, 104, 202, '2021-10-03 08:01:00', '2021-10-03 08:13:00', '2021-10-03 08:31:00', 7.5, 22, 4),
(9005, 105, 203, '2021-10-01 08:02:10', null, '2021-10-01 08:31:00', null, null, null),
(9006, 106, 203, '2021-10-01 18:01:00', '2021-10-01 18:09:00', '2021-10-01 18:31:00', 8.0, 25.5, 5),
(9007, 107, 203, '2021-10-02 11:01:00', '2021-10-02 11:07:00', '2021-10-02 11:31:00', 9.9, 30, 5),
(9008, 108, 203, '2021-10-02 21:01:00', '2021-10-02 21:10:00', '2021-10-02 21:31:00', 13.2, 38, 4),
(9009, 109, 203, '2021-10-08 18:01:00', '2021-10-08 18:11:50', '2021-10-08 18:51:00', 13, 40, 5);
需求
场景逻辑说明：
用户提交打车请求后,在用户打车记录表生成一条打车记录,order_id-The order number is set to null;
当有司机接单时,在打车订单表生成一条订单,填充order_time-The order time and the fields to its left,start_time-The pick-up time and the fields to the right of it are all null,并把order_id-order number andorder_time-接单时间（end_time-打车结束时间）写入打车记录表;若一直无司机接单,超时或中途用户主动取消打车,则记录end_time-打车结束时间.
若乘客上车前,乘客或司机点击取消订单,会将打车订单表对应订单的finish_time-The order completion time is populated with the cancellation time,其余字段设为null.
当司机接上乘客时,填充订单表中该start_time-开始计费的上车时间.
当订单完成时填充订单完成时间、里程数、费用;评分设为null,在用户给司机打1~5星评价后填充.
问题：请找到2021年10月有过取消订单记录的司机,计算他们每人全部已完成的有评分订单的平均评分及总体平均评分,保留1位小数.先按driver_id升序输出,再输出总体情况.
答案
select
coalesce(o.driver_id,'总体') as driver_id,
round(avg(o.grade),1) as avg_grade
from tb_get_car_order o
where driver_id in(
select distinct driver_id
from tb_get_car_order
where date_format(order_time,'%Y%m')=202110 and start_time is null)
group by o.driver_id with rollup
SQL176 每个城市中评分最高的司机信息
建表语句
DROP TABLE IF EXISTS tb_get_car_record,tb_get_car_order;
CREATE TABLE tb_get_car_record (
id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
uid INT NOT NULL COMMENT '用户ID',
city VARCHAR(10) NOT NULL COMMENT '城市',
event_time datetime COMMENT '打车时间',
end_time datetime COMMENT '打车结束时间',
order_id INT COMMENT '订单号'
) CHARACTER SET utf8 COLLATE utf8_bin;
CREATE TABLE tb_get_car_order (
id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
order_id INT NOT NULL COMMENT '订单号',
uid INT NOT NULL COMMENT '用户ID',
driver_id INT NOT NULL COMMENT '司机ID',
order_time datetime COMMENT '接单时间',
start_time datetime COMMENT '开始计费的上车时间',
finish_time datetime COMMENT '订单结束时间',
mileage FLOAT COMMENT '行驶里程数',
fare FLOAT COMMENT '费用',
grade TINYINT COMMENT '评分'
) CHARACTER SET utf8 COLLATE utf8_bin;
INSERT INTO tb_get_car_record(uid, city, event_time, end_time, order_id) VALUES
(101, '北京', '2021-10-01 07:00:00', '2021-10-01 07:02:00', null),
(102, '北京', '2021-10-01 09:00:30', '2021-10-01 09:01:00', 9001),
(101, '北京', '2021-10-01 08:28:10', '2021-10-01 08:30:00', 9002),
(103, '北京', '2021-10-02 07:59:00', '2021-10-02 08:01:00', 9003),
(104, '北京', '2021-10-03 07:59:20', '2021-10-03 08:01:00', 9004),
(105, '北京', '2021-10-01 08:00:00', '2021-10-01 08:02:10', 9005),
(106, '北京', '2021-10-01 17:58:00', '2021-10-01 18:01:00', 9006),
(107, '北京', '2021-10-02 11:00:00', '2021-10-02 11:01:00', 9007),
(108, '北京', '2021-10-02 21:00:00', '2021-10-02 21:01:00', 9008),
(109, '北京', '2021-10-08 18:00:00', '2021-10-08 18:01:00', 9009);
INSERT INTO tb_get_car_order(order_id, uid, driver_id, order_time, start_time, finish_time, mileage, fare, grade) VALUES
(9002, 101, 202, '2021-10-01 08:30:00', null, '2021-10-01 08:31:00', null, null, null),
(9001, 102, 202, '2021-10-01 09:01:00', '2021-10-01 09:06:00', '2021-10-01 09:31:00', 10.0, 41.5, 5),
(9003, 103, 202, '2021-10-02 08:01:00', '2021-10-02 08:15:00', '2021-10-02 08:31:00', 11.0, 41.5, 4),
(9004, 104, 202, '2021-10-03 08:01:00', '2021-10-03 08:13:00', '2021-10-03 08:31:00', 7.5, 22, 4),
(9005, 105, 203, '2021-10-01 08:02:10', null, '2021-10-01 08:31:00', null, null, null),
(9006, 106, 203, '2021-10-01 18:01:00', '2021-10-01 18:09:00', '2021-10-01 18:31:00', 8.0, 25.5, 5),
(9007, 107, 203, '2021-10-02 11:01:00', '2021-10-02 11:07:00', '2021-10-02 11:31:00', 9.9, 30, 5),
(9008, 108, 203, '2021-10-02 21:01:00', '2021-10-02 21:10:00', '2021-10-02 21:31:00', 13.2, 38, 4),
(9009, 109, 203, '2021-10-08 18:01:00', '2021-10-08 18:11:50', '2021-10-08 18:51:00', 13, 40, 5);
需求
场景逻辑说明：
用户提交打车请求后,在用户打车记录表生成一条打车记录,order_id-The order number is set to null;
当有司机接单时,在打车订单表生成一条订单,填充order_time-The order time and the fields to its left,start_time-The pick-up time and the fields to the right of it are all null,并把order_id-order number andorder_time-接单时间（end_time-打车结束时间）写入打车记录表;若一直无司机接单,超时或中途用户主动取消打车,则记录end_time-打车结束时间.
若乘客上车前,乘客或司机点击取消订单,会将打车订单表对应订单的finish_time-The order completion time is populated with the cancellation time,其余字段设为null.
当司机接上乘客时,填充订单表中该start_time-开始计费的上车时间.
当订单完成时填充订单完成时间、里程数、费用;评分设为null,在用户给司机打1~5星评价后填充.
问题：请统计每个城市中评分最高的司机平均评分、日均接单量和日均行驶里程数.
注：有多个司机评分并列最高时,都输出.
平均评分和日均接单量保留1位小数,
日均行驶里程数保留3位小数,按日均接单数升序排序.
' 答案
select city,driver_id,avg_grade,avg_order_num,avg_mileage from
(select r.city,o.driver_id,
round(avg(o.grade),1) avg_grade,
round(count(o.order_id)/(count(distinct date(order_time))),1) avg_order_num,
round(sum(o.mileage)/(count(distinct date(order_time))),3) avg_mileage,
dense_rank() over (partition by r.city order by round(avg(o.grade),1) desc) t_rank
from tb_get_car_order o
inner join tb_get_car_record r on r.order_id=o.order_id
group by r.city,o.driver_id) as a
where t_rank = 1
order by avg_order_num
SQL177 国庆期间近7日日均取消订单量
建表语句
DROP TABLE IF EXISTS tb_get_car_record,tb_get_car_order;
CREATE TABLE tb_get_car_record (
id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
uid INT NOT NULL COMMENT '用户ID',
city VARCHAR(10) NOT NULL COMMENT '城市',
event_time datetime COMMENT '打车时间',
end_time datetime COMMENT '打车结束时间',
order_id INT COMMENT '订单号'
) CHARACTER SET utf8 COLLATE utf8_bin;
CREATE TABLE tb_get_car_order (
id INT PRIMARY KEY AUTO_INCREMENT COMMENT '自增ID',
order_id INT NOT NULL COMMENT '订单号',
uid INT NOT NULL COMMENT '用户ID',
driver_id INT NOT NULL COMMENT '司机ID',
order_time datetime COMMENT '接单时间',
start_time datetime COMMENT '开始计费的上车时间',
finish_time datetime COMMENT '订单结束时间',
mileage FLOAT COMMENT '行驶里程数',
fare FLOAT COMMENT '费用',
grade TINYINT COMMENT '评分'
) CHARACTER SET utf8 COLLATE utf8_bin;
INSERT INTO tb_get_car_record(uid, city, event_time, end_time, order_id) VALUES
(101, '北京', '2021-09-25 08:28:10', '2021-09-25 08:30:00', 9011),
(102, '北京', '2021-09-25 09:00:30', '2021-09-25 09:01:00', 9012),
(103, '北京', '2021-09-26 07:59:00', '2021-09-26 08:01:00', 9013),
(104, '北京', '2021-09-26 07:59:00', '2021-09-26 08:01:00', 9023),
(104, '北京', '2021-09-27 07:59:20', '2021-09-27 08:01:00', 9014),
(105, '北京', '2021-09-28 08:00:00', '2021-09-28 08:02:10', 9015),
(106, '北京', '2021-09-29 17:58:00', '2021-09-29 18:01:00', 9016),
(107, '北京', '2021-09-30 11:00:00', '2021-09-30 11:01:00', 9017),
(108, '北京', '2021-09-30 21:00:00', '2021-09-30 21:01:00', 9018),
(102, '北京', '2021-10-01 09:00:30', '2021-10-01 09:01:00', 9002),
(106, '北京', '2021-10-01 17:58:00', '2021-10-01 18:01:00', 9006),
(101, '北京', '2021-10-02 08:28:10', '2021-10-02 08:30:00', 9001),
(107, '北京', '2021-10-02 11:00:00', '2021-10-02 11:01:00', 9007),
(108, '北京', '2021-10-02 21:00:00', '2021-10-02 21:01:00', 9008),
(103, '北京', '2021-10-02 07:59:00', '2021-10-02 08:01:00', 9003),
(104, '北京', '2021-10-03 07:59:20', '2021-10-03 08:01:00', 9004),
(109, '北京', '2021-10-03 18:00:00', '2021-10-03 18:01:00', 9009);
INSERT INTO tb_get_car_order(order_id, uid, driver_id, order_time, start_time, finish_time, mileage, fare, grade) VALUES
(9011, 101, 211, '2021-09-25 08:30:00', '2021-09-25 08:31:00', '2021-09-25 08:54:00', 10, 35, 5),
(9012, 102, 211, '2021-09-25 09:01:00', '2021-09-25 09:01:50', '2021-09-25 09:28:00', 11, 32, 5),
(9013, 103, 212, '2021-09-26 08:01:00', '2021-09-26 08:03:00', '2021-09-26 08:27:00', 12, 31, 4),
(9023, 104, 213, '2021-09-26 08:01:00', null, '2021-09-26 08:27:00', null, null, null),
(9014, 104, 212, '2021-09-27 08:01:00', '2021-09-27 08:04:00', '2021-09-27 08:21:00', 11, 31, 5),
(9015, 105, 212, '2021-09-28 08:02:10', '2021-09-28 08:04:10', '2021-09-28 08:25:10', 12, 31, 4),
(9016, 106, 213, '2021-09-29 18:01:00', '2021-09-29 18:02:10', '2021-09-29 18:23:00', 11, 39, 4),
(9017, 107, 213, '2021-09-30 11:01:00', '2021-09-30 11:01:40', '2021-09-30 11:31:00', 11, 38, 5),
(9018, 108, 214, '2021-09-30 21:01:00', '2021-09-30 21:02:50', '2021-09-30 21:21:00', 14, 38, 5),
(9002, 102, 202, '2021-10-01 09:01:00', '2021-10-01 09:06:00', '2021-10-01 09:31:00', 10.0, 41.5, 5),
(9006, 106, 203, '2021-10-01 18:01:00', '2021-10-01 18:09:00', '2021-10-01 18:31:00', 8.0, 25.5, 4),
(9001, 101, 202, '2021-10-02 08:30:00', null, '2021-10-02 08:31:00', null, null, null),
(9007, 107, 203, '2021-10-02 11:01:00', '2021-10-02 11:07:00', '2021-10-02 11:31:00', 9.9, 30, 5),
(9008, 108, 204, '2021-10-02 21:01:00', '2021-10-02 21:10:00', '2021-10-02 21:31:00', 13.2, 38, 4),
(9003, 103, 202, '2021-10-02 08:01:00', '2021-10-02 08:15:00', '2021-10-02 08:31:00', 11.0, 41.5, 4),
(9004, 104, 202, '2021-10-03 08:01:00', '2021-10-03 08:13:00', '2021-10-03 08:31:00', 7.5, 22, 4),
(9009, 109, 204, '2021-10-03 18:01:00', null, '2021-10-03 18:51:00', null, null, null);
需求
场景逻辑说明：
用户提交打车请求后,在用户打车记录表生成一条打车记录,order_id-The order number is set to null;
当有司机接单时,在打车订单表生成一条订单,填充order_time-The order time and the fields to its left,start_time-The pick-up time and the fields to the right of it are all null,并把order_id-order number andorder_time-接单时间（end_time-打车结束时间）写入打车记录表;若一直无司机接单,超时或中途用户主动取消打车,则记录end_time-打车结束时间.
若乘客上车前,乘客或司机点击取消订单,会将打车订单表对应订单的finish_time-The order completion time is populated with the cancellation time,其余字段设为null.
当司机接上乘客时,填充订单表中该start_time-开始计费的上车时间.
当订单完成时填充订单完成时间、里程数、费用;评分设为null,在用户给司机打1~5星评价后填充.
问题：请统计国庆头3天里,每天的近7日日均订单完成量和日均订单取消量,按日期升序排序.结果保留2位小数.
答案
SELECT dt, finish_num_7d, cancel_num_7d
FROM (
SELECT dt,
ROUND(AVG(finish_num) over(ORDER BY dt ROWS 6 preceding), 2) as finish_num_7d,
ROUND(AVG(cancel_num) over(ORDER BY dt ROWS 6 preceding), 2) as cancel_num_7d
FROM (
SELECT dt, SUM(is_finish) as finish_num, COUNT(1) - SUM(is_finish) as cancel_num
FROM (
SELECT DATE(order_time) as dt, IF(start_time IS NULL, 0, 1) as is_finish
FROM tb_get_car_order
WHERE DATE(order_time) BETWEEN '2021-09-25' and '2021-10-03'
) as t_order_status
GROUP BY dt
) as t_finish_cancel_daily
)as t_finish_cancel_7d
WHERE dt >= '2021-10-01';
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