From: Paul Austin <paul.austin@automutatio.com>
To: Paul Austin <paul.austin@automutatio.com>,
	"pgsql-general@lists.postgresql.org" <pgsql-general@lists.postgresql.org>
Subject: RE: Extend CREATE POLICY to add IF EXISTS
Thread-Topic: Extend CREATE POLICY to add IF EXISTS
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Date: Mon, 20 Oct 2025 21:49:12 +0000
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I forgot DROP POLICY already has IF EXISTS

From: Paul Austin <paul.austin@automutatio.com>
Sent: October 20, 2025 2:46 PM
To: pgsql-general@lists.postgresql.org
Subject: Extend CREATE POLICY to add IF EXISTS

Many (but not all) DDL statements use the pattern IF EXISTS or IF NOT EXIST=
S. This is really useful if you want to create a re-start-able data model u=
pdate script without needing to have PL/pgSQL blocks that has checks to see=
 if it exists.

An example of a statement that doesn't implement this pattern in the CREATE=
 POLICY statement.

Is there a plan to add this pattern to the rest of the DDL statements? Or c=
ould it be added to the CREATE/DROP POLICY statements?

Thanks,
Paul

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<p class=3D"MsoNormal">I forgot DROP POLICY already has IF EXISTS<o:p></o:p=
></p>
<p class=3D"MsoNormal"><o:p>&nbsp;</o:p></p>
<div>
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<p class=3D"MsoNormal"><b><span lang=3D"EN-US" style=3D"font-family:&quot;C=
alibri&quot;,sans-serif;mso-ligatures:none;mso-fareast-language:EN-CA">From=
:</span></b><span lang=3D"EN-US" style=3D"font-family:&quot;Calibri&quot;,s=
ans-serif;mso-ligatures:none;mso-fareast-language:EN-CA"> Paul
 Austin &lt;paul.austin@automutatio.com&gt; <br>
<b>Sent:</b> October 20, 2025 2:46 PM<br>
<b>To:</b> pgsql-general@lists.postgresql.org<br>
<b>Subject:</b> Extend CREATE POLICY to add IF EXISTS<o:p></o:p></span></p>
</div>
</div>
<p class=3D"MsoNormal"><o:p>&nbsp;</o:p></p>
<p class=3D"MsoNormal">Many (but not all) DDL statements use the pattern IF=
 EXISTS or IF NOT EXISTS. This is really useful if you want to create a re-=
start-able data model update script without needing to have PL/pgSQL blocks=
 that has checks to see if it exists.<o:p></o:p></p>
<p class=3D"MsoNormal"><o:p>&nbsp;</o:p></p>
<p class=3D"MsoNormal">An example of a statement that doesn&#8217;t impleme=
nt this pattern in the CREATE POLICY statement.<o:p></o:p></p>
<p class=3D"MsoNormal"><o:p>&nbsp;</o:p></p>
<p class=3D"MsoNormal">Is there a plan to add this pattern to the rest of t=
he DDL statements? Or could it be added to the CREATE/DROP POLICY statement=
s?<o:p></o:p></p>
<p class=3D"MsoNormal"><o:p>&nbsp;</o:p></p>
<p class=3D"MsoNormal">Thanks,<o:p></o:p></p>
<p class=3D"MsoNormal">Paul<o:p></o:p></p>
</div>
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