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<title>2.9.Deletions</title>
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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="tutorial-delete"></a>2.9.Deletions</h2></div></div></div>
<a name="id569532"></a><p> Rows can be removed from a table using the <code class="command">DELETE</code>
command.
Suppose you are no longer interested in the weather of Hayward.
Then you can do the following to delete those rows from the table:
</p>
<pre class="programlisting">DELETE FROM weather WHERE city = 'Hayward';</pre>
<p>
All weather records belonging to Hayward are removed.
</p>
<pre class="programlisting">SELECT * FROM weather;</pre>
<p>
</p>
<pre class="screen"> city | temp_lo | temp_hi | prcp | date
---------------+---------+---------+------+------------
San Francisco | 46 | 50 | 0.25 | 1994-11-27
San Francisco | 41 | 55 | 0 | 1994-11-29
(2 rows)</pre>
<p>
</p>
<p> One should be wary of statements of the form
</p>
<pre class="synopsis">DELETE FROM <em class="replaceable"><code>tablename</code></em>;</pre>
<p>
Without a qualification, <code class="command">DELETE</code> will
remove <span class="emphasis"><em>all</em></span> rows from the given table, leaving it
empty. The system will not request confirmation before
doing this!
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