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the SELECT Basics
This tutorial introduces the SQL language. We will use the SELECT statement. We will use the WORLD table
name: Country name
continent: Africa copies
area: the area of
population: population
gdp: Gross Domestic Product
1. Find Germany Germany's population.
SELECT population FROM world WHERE name = ' Germany'
2, the query area of over 5,000,000 square kilometers of the country, displaying her name and per capita gross domestic product (gdp / population) for each country.
select name, gdp / population from world where area> 5000000
3, display "Ireland Irish", "Iceland Iceland", "Denmark Denmark," the name of the country and population. (Check the list: the word "IN" allows us to check whether an item in the list.)
The SELECT name, the WHERE world name in the FROM Population ( 'Ireland', 'Iceland', 'Denmark')
4, to show the area of the country name between 200,000 and 250,000 and an area of the country.
SELECT name, area FROM world where area between 200000 and 250000
