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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML
><HEAD
><TITLE
>Deletions</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet version 1.19"><LINK
REL="HOME"
TITLE="PostgreSQL User's Guide"
HREF="user.html"><LINK
REL="UP"
TITLE="The Query Language"
HREF="query-ug.html"><LINK
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TITLE="Updates"
HREF="query-ug2935.html"><LINK
REL="NEXT"
TITLE="Using Aggregate Functions"
HREF="query-ug2946.html"></HEAD
><BODY
BGCOLOR="#FFFFFF"
TEXT="#000000"
><DIV
CLASS="NAVHEADER"
><TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
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><TR
><TH
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>PostgreSQL User's Guide</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
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>Prev</A
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><TD
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>Chapter 12. The Query Language</TD
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>Next</A
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><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><H1
CLASS="SECT1"
><A
NAME="AEN2939"
>Deletions</A
></H1
><P
>     Deletions are performed using the <B
CLASS="COMMAND"
>delete</B
> command:
<PRE
CLASS="PROGRAMLISTING"
>DELETE FROM weather WHERE city = 'Hayward';</PRE
>

     All weather recording belongs to Hayward is removed.
     One should be wary of queries of the form
<PRE
CLASS="PROGRAMLISTING"
>DELETE FROM classname;</PRE
>

     Without a qualification, <B
CLASS="COMMAND"
>delete</B
> will simply
     remove  all  instances  of  the given class, leaving it
     empty.  The system will not request confirmation before
     doing this.</P
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
WIDTH="100%"
BORDER="0"
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><A
HREF="query-ug2935.html"
>Prev</A
></TD
><TD
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ALIGN="center"
VALIGN="top"
><A
HREF="user.html"
>Home</A
></TD
><TD
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><A
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>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>Updates</TD
><TD
WIDTH="34%"
ALIGN="center"
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><A
HREF="query-ug.html"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>Using Aggregate Functions</TD
></TR
></TABLE
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>