LeetCode刷题:595.Big Countries


595. Big Countries

SQL架构

Create table If Not Exists World (name varchar(255), continent varchar(255), area int, population int, gdp int)
Truncate table World
insert into World (name, continent, area, population, gdp) values ('Afghanistan', 'Asia', '652230', '25500100', '20343000000')
insert into World (name, continent, area, population, gdp) values ('Albania', 'Europe', '28748', '2831741', '12960000000')
insert into World (name, continent, area, population, gdp) values ('Algeria', 'Africa', '2381741', '37100000', '188681000000')
insert into World (name, continent, area, population, gdp) values ('Andorra', 'Europe', '468', '78115', '3712000000')
insert into World (name, continent, area, population, gdp) values ('Angola', 'Africa', '1246700', '20609294', '100990000000')

There is a table World

name continent area population gdp
Afghanistan Asia 652230 25500100 20343000
Albania Europe 28748 2831741 12960000
Algeria Africa 2381741 37100000 188681000
Andorra Europe 468 78115 3712000
Angola Africa 1246700 20609294 100990000

A country is big if it has an area of bigger than 3 million square km or a population of more than 25 million.
Write a SQL solution to output big countries’ name, population and area.
For example, according to the above table, we should output:

name population area
Afghanistan 25500100 652230
Algeria 37100000 2381741
解题思路:

利用人口和面积进行筛选

解答:
select name, population, area from World where area > 3000000 or population > 25000000;

文章作者: Jason
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