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>Chapter 2. The <ACRONYM
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>2.9. Deletions</A
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><P
>    Rows can be removed from a table using the <TT
CLASS="COMMAND"
>DELETE</TT
>
    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 <TT
CLASS="REPLACEABLE"
><I
>tablename</I
></TT
>;</PRE
><P>

    Without a qualification, <TT
CLASS="COMMAND"
>DELETE</TT
> will
    remove  <SPAN
CLASS="emphasis"
><I
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>all</I
></SPAN
>  rows from the given table, leaving it
    empty.  The system will not request confirmation before
    doing this!
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