SQL Project Planning in SQL HackerRank Solution

 

SELECT START_DATE, MIN(END_DATE)

FROM

(SELECT START_DATE

FROM PROJECTS

WHERE START_DATE NOT IN

(SELECT END_DATE

FROM PROJECTS)) A,

(SELECT END_DATE

FROM PROJECTS

WHERE END_DATE NOT IN

(SELECT START_DATE

FROM PROJECTS)) B

WHERE START_DATE < END_DATE

GROUP BY START_DATE

ORDER BY (MIN(END_DATE) - START_DATE), START_DATE;