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| − | ==BBC Country Profiles==
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| − | This tutorial introduces SQL as a query language. We will be using the SELECT command on the table bbc:
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| − | <table style='' border='1'><tr>
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| − | <th>name</th>
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| − | <th>region</th>
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| − | <th>area</th>
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| − | <th>population</th>
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| − | <th>gdp</th>
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| − | </tr>
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| − | <tr>
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| − | <td>Afghanistan</td>
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| − | <td>South Asia</td>
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| − | <td align='right'>652225</td>
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| − | <td align='right'>26000000</td>
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| − | <td></td>
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| − | </tr>
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| − | <tr>
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| − | <td>Albania</td>
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| − | <td>Europe</td>
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| − | <td align='right'>28728</td>
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| − | <td align='right'>3200000</td>
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| − | <td align='right'>6656000000</td>
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| − | </tr>
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| − | <tr>
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| − | <td>Algeria</td>
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| − | <td>Middle East</td>
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| − | <td align='right'>2400000</td>
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| − | <td align='right'>32900000</td>
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| − | <td align='right'>75012000000</td>
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| − | </tr>
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| − | <tr>
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| − | <td>Andorra</td>
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| − | <td>Europe</td>
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| − | <td align='right'>468</td>
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| − | <td align='right'>64000</td>
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| − | <td></td>
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| − | </tr>
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| − | <tr>
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| − | <td colspan='5'>...</td>
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| − | </tr>
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| − | </table>
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| − | ==Exercises==
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| − | Using the <code>SELECT</code> statement.
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| | | | |
| − | <div class='qu'>
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| − | [[Read the notes about this table.]]
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| − | Issue the command:
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| − | SELECT name, region, population FROM bbc
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| − | Look at the output.
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| − | <source lang='sql' class='def'>
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| − | SELECT name, region, population FROM bbc
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| − | </source>
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| − |
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| − | <source lang='sql' class='ans'>
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| − | SELECT name, region, population FROM bbc
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| − | </source>
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| − | </div>
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| − |
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| − |
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| − | <div class='qu'>
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| − | Show the name for the countries that have a population of at least 200 million. (200 million is 200000000, there are eight zeros)
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| − | <source lang='sql' class='def'>
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| − | SELECT name FROM bbc
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| − | WHERE population>250000000
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| − | </source>
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| − |
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| − | <source lang='sql' class='ans'>
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| − | SELECT name FROM bbc
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| − | WHERE population>200000000
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| − | </source>
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| − | </div>
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