MySQL

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

SELECT ROUND(MAX(LAT_N)-MIN(LAT_N) + MAX(LONG_W)-MIN(LONG_W),4)

FROM STATION

SELECT ROUND(ABS(A - C) + ABS(B - D),4) AS MD FROM ( SELECT MIN(LAT_N) AS A, MAX(LAT_N) AS C, MIN(LONG_W) AS B, MAX(LONG_W) AS D FROM STATION ) AS sub;

MySQL

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

-- so basicaly: |x1 - x2| + |y1 - y2| select cast(abs(min(lat_n) - max(lat_n)) as decimal (38,4)) + cast(abs(min(long_w) - max(long_w)) as decimal (38,4)) from station