MySQL 8.0

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CREATE TABLE tickets(
   tid                INTEGER  NOT NULL PRIMARY KEY 
  ,created_At          VARCHAR(23) NOT NULL
  ,apply_sla          BIT  NOT NULL
  ,ticket_closed_date VARCHAR(25) NOT NULL
  ,days_to_complete   INTEGER  NOT NULL
);
INSERT INTO tickets(tid,created_At,apply_sla,ticket_closed_date,days_to_complete) VALUES (100,'2020-10-02 00:00:00',1,'2020-10-09 00:00:00',3);
CREATE TABLE holidays(
   id           INTEGER  NOT NULL PRIMARY KEY 
  ,holiday_date DATE  NOT NULL
  ,end_date     DATE  NOT NULL
);
INSERT INTO holidays(id,holiday_date,end_date) VALUES (20,'2020-10-05','2020-10-05');
with recursive cte_tickets as (
    select tid, created_at as dt, ticket_closed_date
    from tickets 
    where apply_sla = 1
    union all
    select tid, dt + interval 1 day, ticket_closed_date
    from cte_tickets
    where dt < ticket_closed_date
)
select t.*, 
    t.created_at 
        + interval (t.days_to_complete + sum(weekday(dt) in (5, 6) or h.holiday_date is not null)) day
        as expected_due_date,    
	count(*) - sum(weekday(dt) in (5, 6) or h.holiday_date is not null) - 1 completed_in,
    t.ticket_closed_date <= t.created_at 
        + interval (t.days_to_complete + sum(weekday(dt) in (5, 6) or h.holiday_date is not null)) day
        as is_sla_met
from tickets t
inner join cte_tickets ct on ct.tid = t.tid
left join holidays h on ct.dt between h.holiday_date and h.end_date
group by t.tid


tid
created_At
apply_sla
ticket_closed_date
days_to_complete
expected_due_date
completed_in
is_sla_met


100
2020-10-02 00:00:00
1
2020-10-09 00:00:00
3
2020-10-08 00:00:00
4
0