✨ Day 28 - Programmers SQL 난이도 4 (#82)

* ✨ Day 28 - Programmers SQL 난이도 4

* 📗 class 명 변경

형민/day_28_case_when_join.txt

@@ -0,0 +1,37 @@
+1번 : 자동차 대여 기록 별 대여 금액 구하기
+ - SELECT
+       HISTORY_ID,
+       ROUND(PERIOD * (1 - IFNULL(DISCOUNT_RATE,0)/100) * DAILY_FEE)  as FEE
+   FROM CAR_RENTAL_COMPANY_CAR crcc
+   LEFT JOIN
+           (SELECT HISTORY_ID, CAR_ID, (DATEDIFF(END_DATE, START_DATE) + 1) as PERIOD, CASE
+               WHEN DATEDIFF(end_date, start_date) + 1 >= 90 THEN '90일 이상'
+               WHEN DATEDIFF(end_date, start_date) + 1 >= 30 THEN '30일 이상'
+               WHEN DATEDIFF(end_date, start_date) + 1 >= 7 THEN '7일 이상'
+           ELSE null END AS DURATION_TYPE
+           FROM CAR_RENTAL_COMPANY_RENTAL_HISTORY) as ccrh
+       ON  ccrh.CAR_ID = crcc.CAR_ID
+   LEFT JOIN CAR_RENTAL_COMPANY_DISCOUNT_PLAN discount
+       ON ccrh.DURATION_TYPE = discount.DURATION_TYPE
+       AND crcc.CAR_TYPE = discount.CAR_TYPE
+   WHERE crcc.CAR_TYPE = '트럭'
+   ORDER BY FEE DESC, HISTORY_ID DESC
+
+2번 : 특정 기간동안 대여 가능한 자동차들의 대여비용 구하기
+
+ - SELECT
+          crcc.CAR_ID,
+          crcc.CAR_TYPE,
+          ROUND(30 * (1 - DISCOUNT_RATE/100) * DAILY_FEE) as FEE
+   FROM CAR_RENTAL_COMPANY_CAR crcc
+   INNER JOIN CAR_RENTAL_COMPANY_DISCOUNT_PLAN ccdp
+       ON ccdp.CAR_TYPE = crcc.CAR_TYPE AND ccdp.DURATION_TYPE = '30일 이상'
+   WHERE crcc.CAR_TYPE IN ('세단', 'SUV')
+       AND ROUND(30 * (1 - DISCOUNT_RATE/100) * DAILY_FEE) >= 500000
+       AND ROUND(30 * (1 - DISCOUNT_RATE/100) * DAILY_FEE) <=  2000000
+       AND crcc.CAR_ID NOT IN
+           (SELECT CAR_ID
+            FROM CAR_RENTAL_COMPANY_RENTAL_HISTORY
+            WHERE start_date < '2022-11-30 00:00:00' AND end_date > '2022-11-01 00:00:00')
+   GROUP BY crcc.CAR_ID
+   ORDER BY FEE DESC, crcc.CAR_TYPE ASC, crcc.CAR_ID DESC