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SQL架构
1 Create table If Not Exists World (name varchar(255), continent varchar(255), area int, population int, gdp int) 2 Truncate table World 3 insert into World (name, continent, area, population, gdp) values (\'Afghanistan\', \'Asia\', \'652230\', \'25500100\', \'20343000000\') 4 insert into World (name, continent, area, population, gdp) values (\'Albania\', \'Europe\', \'28748\', \'2831741\', \'12960000000\') 5 insert into World (name, continent, area, population, gdp) values (\'Algeria\', \'Africa\', \'2381741\', \'37100000\', \'188681000000\') 6 insert into World (name, continent, area, population, gdp) values (\'Andorra\', \'Europe\', \'468\', \'78115\', \'3712000000\') 7 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 | +--------------+-------------+--------------+
这里有张 World 表
+-----------------+------------+------------+--------------+---------------+ | 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 | +-----------------+------------+------------+--------------+---------------+
如果一个国家的面积超过300万平方公里，或者人口超过2500万，那么这个国家就是大国家。
编写一个SQL查询，输出表中所有大国家的名称、人口和面积。
例如，根据上表，我们应该输出:
+--------------+-------------+--------------+ | name | population | area | +--------------+-------------+--------------+ | Afghanistan | 25500100 | 652230 | | Algeria | 37100000 | 2381741 | +--------------+-------------+--------------+
1613ms
1 # Write your MySQL query statement below 2 select 3 a.name, a.population, a.area 4 from 5 world as a 6 where 7 a.area > 3000000 or a.population > 25000000
1627ms
1 # Write your MySQL query statement below 2 select w.name, w.population, w.area 3 from World w 4 where w.area > 3000000 or 5 w.population > 25000000;