时间序列题型+explode(爆炸函数的使用)

根据下图中的数据，请编写SQL找出申请日期到受理日期间超过10个工作日（包含10个工作日）的ID有哪些？

表1

表2

 建表语句:

create table tab1 (dt string, isworkday string) ;
insert into tab1
values ('2020-06-1', 'Y'),
       ('2020-06-2', 'Y'),
       ('2020-06-3', 'Y'),
       ('2020-06-4', 'Y'),
       ('2020-06-5', 'Y'),
       ('2020-06-6', 'N'),
       ('2020-06-7', 'N'),
       ('2020-06-8', 'Y'),
       ('2020-06-9', 'Y'),
       ('2020-06-10', 'Y'),
       ('2020-06-11', 'Y'),
       ('2020-06-12', 'Y'),
       ('2020-06-13', 'N'),
       ('2020-06-14', 'N'),
       ('2020-06-15', 'Y'),
       ('2020-06-16', 'Y'),
       ('2020-06-17', 'Y'),
       ('2020-06-18', 'Y'),
       ('2020-06-19', 'Y'),
       ('2020-06-20', 'N'),
       ('2020-06-21', 'N'),
       ('2020-06-22', 'Y'),
       ('2020-06-23', 'Y'),
       ('2020-06-24', 'Y'),
       ('2020-06-25', 'N'),
       ('2020-06-26', 'N'),
       ('2020-06-27', 'N'),
       ('2020-06-28', 'Y'),
       ('2020-06-29', 'Y'),
       ('2020-06-30', 'Y');
create table tab2 (id int, startdate string, enddate string) ;
insert into tab2 values (1, '2020-06-02', '2020-06-08'),
       (2, '2020-06-03', '2020-06-26'),
       (3, '2020-06-05', '2020-06-15'),
       (4, '2020-06-15', '2020-06-30'),
       (5, '2020-06-18', '2020-06-27');

select * from tab1;
select * from tab2;

需求:

编写SQL找出申请日期到受理日期间超过10个工作日（包含10个工作日）的ID有哪些？

分析思路:对于两个时间段列举出来具体的日期用sequence函数

sequence(to_date(startdate), to_date(enddate), interval 1 day

再通过类似于行转列,就是 explode()函数,不是完全的行转列==> explode()函数  接着过滤掉周末再求和

最终SQL语句:

select sequence() from tab2;
with t1 as (
    SELECT id,
           explode(sequence(to_date(startdate), to_date(enddate), interval 1 day)) day
from tab2
)
select id,
       count(day) as days
from t1 join tab1
on t1. day=to_date(tab1.dt)
where isworkday='Y'
group by id
having count(day) >=10
order by id
;