UC知道SQL初级问题
来源：百度知道 编辑：UC知道 时间：2024/07/02 02:25:03
现在有一张表：bbc(countryName, region, area, population, gdp)
问题是：For each region show the region and number of countries with populations of at least 10 million.
我写的答案是：
select region,count(population>=10000000) from bbc group by region
但是提示说有错误，我不知道哪里出错了，求教~
select region,count(countryName) from bbc group by region having population>10000000
这么写也错,求教啦
问题是：For each region show the region and number of countries with populations of at least 10 million.
我写的答案是：
select region,count(population>=10000000) from bbc group by region
但是提示说有错误，我不知道哪里出错了，求教~
select region,count(countryName) from bbc group by region having population>10000000
这么写也错,求教啦
要求是找出每个地区人数大於10M的城市数目
select region,count(countryName) from bbc
where population>=10000000
group by region
写 count(population>=10000000)
count这种语句的时候最好不要跟上其他字段
select count(countryName) from bbc group by region having population>10000000
select count(population>=10000000) from bbc group by region
不知道不是这个问题你试试看
确认population 这个字段是不是都是数字，如果不是数字或者为null都会出错