From: Paul Austin <paul.austin@automutatio.com>
To: "pgsql-general@lists.postgresql.org" <pgsql-general@lists.postgresql.org>
Subject: 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 21:45:56 +0000
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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">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>
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