sql notes: hackerrank weather observation station 18

Problem

Consider P₁(a,b) and P₂(c,d) to be two points on a 2D plane.

• a happens to equal the minimum value in Northern Latitude (LAT_N in STATION).
• b happens to equal the minimum value in Western Longitude (LONG_W in STATION).
• c happens to equal the maximum value in Northern Latitude (LAT_N in STATION).
• d happens to equal the maximum value in Western Longitude (LONG_W in STATION).

Query the Manhattan Distance between points P₁ and P₂ and round it to a scale of 4 decimal places.

Input Format
The STATION table is described as follows:

where LAT_N is the northern latitude and LONG_W is the western longitude.

Analysis

The Manhattan Distance is |x₁ - x₂| + |y₁ - y₂| = |a - c| + |b - d|.

• |a - c| + |b - d| ==> ABS(MIN(LAT_N)-MAX(LAT_N)) + ABS(MIN(LONG_W)-MAX(LONG_W))
• round to a scale of 4 decimal places ==> SELECT ROUND(ABS(MIN(LAT_N)-MAX(LAT_N)) + ABS(MIN(LONG_W)-MAX(LONG_W)), 4)
• from STATION table ==> FROM STATION

Solution

1

SELECT ROUND(ABS(MIN(LAT_N)-MAX(LAT_N)) + ABS(MIN(LONG_W)-MAX(LONG_W)), 4) FROM STATION;

Link

Weather Observation Station 18
(中文版) SQL 笔记: Hackerrank Weather Observation Station 18