Difference between revisions of "SELECT Reference"

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The output from a SELECT statement is always a grid - with a number of rows and a number of columns.
 
The output from a SELECT statement is always a grid - with a number of rows and a number of columns.
 
The simplest SELECT commands involve a single table:
 
The simplest SELECT commands involve a single table:
<div class='ht'>
+
<source lang='sql'>
<source lang='sql' class='def'>
+
 
SELECT name, population
 
SELECT name, population
 
   FROM bbc
 
   FROM bbc
 
  WHERE region='North America'
 
  WHERE region='North America'
 
</source>
 
</source>
</div>
+
<table class="sqlmine"><tbody><tr><th>name</th><th>population</th></tr><tr><td>Canada</td><td class="r">32000000</td></tr><tr><td>Mexico</td><td class="r">106400000</td></tr><tr><td>United States of America</td><td class="r">295000000</td></tr></tbody></table>
 +
*The SELECT line determines which columns to show - in this case <code>name</code> and <code>population</code>, both of which are columns of the bbc ta le.
 +
*The WHERE clause determines which rows to show

Revision as of 11:07, 11 August 2012

The SELECT command is used to show data from a database.

The output from a SELECT statement is always a grid - with a number of rows and a number of columns. The simplest SELECT commands involve a single table:

SELECT name, population
  FROM bbc
 WHERE region='North America'
<tbody></tbody>
namepopulation
Canada32000000
Mexico106400000
United States of America295000000
  • The SELECT line determines which columns to show - in this case name and population, both of which are columns of the bbc ta le.
  • The WHERE clause determines which rows to show
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