Difference between revisions of "SELECT"

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A SELECT statement gets data from a table. Each table contains rows and columns - you can SELECT some columns and ignore others
 
*The column names on the select line control which columns you get
 
*The FROM clause controls which table you access
 
<div class=params>schema:scott</div>
 
The table <code>games</code> shows the year and the city hosting the Olympic Games.
 
<table border='1'>
 
<caption>games</caption>
 
<tr> <th>yr</th> <th>city</th> <th>y1</th></tr>
 
<tr> <td align='right'>2000</td> <td>Sydney</td>  <td></td></tr>
 
<tr> <td align='right'>2004</td> <td>Athens</td> <td>2000</td></tr>
 
<tr> <td align='right'>2008</td> <td>Beijing</td><td>2004</td> </tr>
 
<tr> <td align='right'>2012</td> <td>London</td><td>2008</td> </tr>
 
</table>
 
<div class=qu>
 
The SELECT statement returns results from a <i>table</i>.
 
In this example the table is <code>games</code> and the columns are
 
<code>yr</code> and <code>city</code>.
 
<div class=tidy>
 
DROP TABLE games;
 
</div>
 
<div class=setup>
 
CREATE TABLE games(yr INT, city VARCHAR(20));
 
INSERT INTO games(city,yr) VALUES ('ouroalpha',2000);
 
INSERT INTO games(city,yr) VALUES ('Athens',2004);
 
INSERT INTO games(city,yr) VALUES ('Beijing',2008);
 
INSERT INTO games(city,yr) VALUES ('London',2012);
 
</div>
 
<div class=def>
 
SELECT yr, city FROM games
 
</div>
 
</div>
 
  
===See also:===
 
*[http://sqlzoo.net/w/index.php/SELECT_from_BBC_Tutorial SELECT Tutorial] - practice using the SELECT command
 
*[SELECT_.._WHERE  |SELECT ... WHERE] - the WHERE clause allows you to get some rows but not others
 

Latest revision as of 04:00, 17 April 2014

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