Difference between revisions of "SQLZOO:SELECT from WORLD Tutorial"
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<li>You can learn about nested statements, these are instructive and entertaining, but not essential for beginners. | <li>You can learn about nested statements, these are instructive and entertaining, but not essential for beginners. | ||
[[SELECT_within_SELECT_Tutorial |Nested <code>SELECT</code> statements | [[SELECT_within_SELECT_Tutorial |Nested <code>SELECT</code> statements using the | ||
<code>world</code> table.]]</li> | <code>world</code> table.]]</li> | ||
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Revision as of 15:58, 15 February 2013
name | continent | area | population | gdp |
---|---|---|---|---|
Afghanistan | Asia | 652230 | 25500100 | 20343000000 |
Albania | Europe | 28748 | 2831741 | 12960000000 |
Algeria | Africa | 2381741 | 37100000 | 188681000000 |
Andorra | Europe | 468 | 78115 | 3712000000 |
Angola | Africa | 1246700 | 20609294 | 100990000000 |
... |
World Country Profiles
In this tutorial you will use the SELECT command on the table World
:
Warming up
Read the notes about this table. Observe the result of running a simple SQL command.
SELECT name, continent, population FROM world
SELECT name, continent, population FROM world
Large Countries
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>250000000
SELECT name FROM world
WHERE population>200000000
Give the name and the per capita GDP for those countries with a population of at least 200 million.
per capita GDP is the GDP divided by the population GDP/population
SELECT name, gdp/population FROM world
WHERE population > 200000000
Show the name
and population
in millions for the countries of 'South America'
Divide the population by 1000000 to get population in millions.
SELECT name, population/1000000 FROM world
WHERE continent='South America'
Show the name
and population
for 'France', 'Germany', 'Italy'
SELECT name, population FROM world
WHERE name IN ('France','Germany','Italy')
Identify the countries which have names including the word 'United'
SELECT name FROM world
WHERE name LIKE '%United%'
What Next
- You can play a game: Find the duplicate
- You can to continue practising the the same techniques
and gain more experience of the basic skills on the Nobel table.
The
WHERE
statement using thenobel
table. - You can learn about nested statements, these are instructive and entertaining, but not essential for beginners.
Nested
SELECT
statements using theworld
table.