[HackerRank] SQL Basic (easy)(5)

1. Weather Observation Station 13

https://www.hackerrank.com/challenges/weather-observation-station-13/problem?isFullScreen=true

Weather Observation Station 13 | HackerRank

SELECT
    TRUNCATE(SUM(LAT_N), 4) AS SUM_LAT
FROM STATION
WHERE LAT_N BETWEEN 38.7880 AND 137.2345

POINT!

TRUNCATE(number, decimals)

: 숫자나 날짜에서 지정한 자리까지 잘라내는(버림하는) 함수
남는 자리는 그대로 버리고, 올림이나 반올림을 하지 않음

 

• number: 자를 대상 숫자
• decimals: 남길 소수점 자리 수 (0 또는 음수도 가능)

 

2. Weather Observation Station 14

https://www.hackerrank.com/challenges/weather-observation-station-14/problem?isFullScreen=true

Weather Observation Station 14 | HackerRank

Query the greatest value of the Northern Latitudes (LAT_N) from STATION that is less than 137.2345. Truncate your answer to  decimal places.

SELECT
    TRUNCATE(MAX(LAT_N), 4) AS MAX_LAT
FROM 
    STATION
WHERE
    LAT_N < 137.2345

3. Weather Observation Station 15

https://www.hackerrank.com/challenges/weather-observation-station-15/problem?isFullScreen=true

Weather Observation Station 15 | HackerRank

Query the Western Longitude (LONG_W) for the largest Northern Latitude (LAT_N) in STATION that is less than 137.2345 . Round your answer to  4 decimal places.

SELECT
    ROUND(LONG_W, 4) AS LON
FROM 
    STATION
WHERE 
    LAT_N < 137.2345
ORDER BY 
	LAT_N DESC
LIMIT 1;

4. Weather Observation Station 16

https://www.hackerrank.com/challenges/weather-observation-station-16/problem?isFullScreen=true

Weather Observation Station 16 | HackerRank

Query the smallest Northern Latitude (LAT_N) from STATION that is greater than 38.7780 . Round your answer to  4 decimal places.

SELECT
    ROUND(MIN(LAT_N), 4) AS MIN_LAT
FROM 
    STATION
WHERE 
    LAT_N > 38.7780

5. Weather Observation Station 17

https://www.hackerrank.com/challenges/weather-observation-station-17/problem?isFullScreen=true

Weather Observation Station 17 | HackerRank

Query the Western Longitude (LONG_W)where the smallest Northern Latitude (LAT_N) in STATION is greater than 38.7780. Round your answer to 4 decimal places.

SELECT
    ROUND(LONG_W, 4) AS MIN_LOG
FROM 
    STATION
WHERE 
	LAT_N > 38.7780
ORDER BY  
	LAT_N ASC
LIMIT 1;