Difference between revisions of "SQLZOO:SELECT from WORLD Tutorial"
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[[Read_the_notes_about_this_table. |Read the notes about this table.]] Observe the result of running a simple SQL command. | [[Read_the_notes_about_this_table. |Read the notes about this table.]] Observe the result of running a simple SQL command. | ||
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[[WHERE_filters |How to use WHERE to filter records.]] | [[WHERE_filters |How to use WHERE to filter records.]] | ||
Show the name for the countries that have a population of at least 200 million. | Show the name for the countries that have a population of at least 200 million. | ||
200 million is 200000000, there are eight zeros. | 200 million is 200000000, there are eight zeros. | ||
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[[SELECT_within_SELECT_Tutorial |Nested <code>SELECT</code> statements using the | [[SELECT_within_SELECT_Tutorial |Nested <code>SELECT</code> statements using the | ||
<code>world</code> table.]]</li> | <code>world</code> table.]]</li> | ||
</ul> |
Revision as of 20:07, 30 April 2015
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 |
... |
Country Profile
In this tutorial you will use the SELECT command on the table World
:
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
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 the continent
'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')
Show the countries which have a name
that includes 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.