SQL ZOO 练习 —— SELECT from WORLD Tutorial

1.Read the notes about this table. Observe the result of running this SQL command to show the name, continent and population of all countries.

SELECT name, continent, population FROM world

2.How to use WHERE to filter records. Show the name for the countries that have a population of at least 200 million. 200 million is 200000000, there are eight zeros.

SELECT name FROM world
WHERE population >= 200000000

3.Give the name and the per capita GDP for those countries with a population of at least 200 million.

HELP:How to calculate per capita GDP
per capita GDP is the GDP divided by the population GDP/population

SELECT name ,GDP/population AS 'per capita GDP'
FROM world
WHERE population >= 200000000

4.Show the name and population in millions for the countries of the continent ‘South America’. Divide the population by 1000000 to get population in millions.

SELECT name,population