mysql - 带 ROUND 和除法的 sql 查询

Question

Show the name and per-capita GDP for those countries with a GDP of at least one trillion (1000000000000; that is 12 zeros). Round this value to the nearest 1000. Show per-capita GDP for the trillion dollar countries to the nearest $1000.

SELECT name ,
       ROUND(gdp/population,0.01)

from world
where gdp >= 1000000000000

但这会产生错误。

任务可测试here

Answer 1

round 的第二个参数是小数点之后或之前的位数。我会从以下开始:

select name ,
       ROUND(gdp/population, -3)
from world
where gdp >= 1000000000000

负数位于小数点之前。您可以阅读documentation .