Thread
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Re: [PATCH] Add pg_get_policy_ddl() function to reconstruct CREATE POLICY statement
Japin Li <japinli@hotmail.com> — 2026-05-22T16:24:54Z
Hi, Akshay On Fri, 22 May 2026 at 19:02, Akshay Joshi <akshay.joshi@enterprisedb.com> wrote: > Hi hackers, > > > Following the recently committed pg_get_database_ddl(), which adopted a VARIADIC options text[] style for > DDL-reconstruction functions, here is a patch in the same spirit for row-level security policies. > > The new function: > pg_get_policy_ddl(table regclass, policy_name name, VARIADIC options text[]) RETURNS setof text > > Reconstructs the CREATE POLICY statement for the named policy on the given table, returning the result as a single row. > > The currently supported option is pretty (boolean) for formatted output. > > SELECT * FROM pg_get_policy_ddl('rls_table', 'pol1'); > SELECT * FROM pg_get_policy_ddl('rls_table', 'pol1', 'pretty', 'true'); > > NULL inputs for table or policy_name return no rows. Unknown option names, invalid boolean values, and duplicate options > are reported as errors consistent with the pattern established by pg_get_database_ddl(). > > The patch includes documentation updates in func-info.sgml and regression tests in rowsecurity.sql covering > PERMISSIVE/RESTRICTIVE, each command type (ALL/SELECT/INSERT/UPDATE/DELETE), TO role lists, both USING and WITH CHECK > clauses, pretty/non-pretty output, and the error paths above. > > Patch is ready for review. > > On Mon, Jan 5, 2026 at 8:00 PM jian he <jian.universality@gmail.com> wrote: > > On Thu, Nov 20, 2025 at 5:27 PM Akshay Joshi > <akshay.joshi@enterprisedb.com> wrote: > > > > Attached is the v8 patch for your review, with updated variable names and a rebase applied. > > > hi. > > + <tbody> > + <row> > + <entry role="func_table_entry"><para role="func_signature"> > + <indexterm> > + <primary>pg_get_policy_ddl</primary> > + </indexterm> > + <function>pg_get_policy_ddl</function> > + ( <parameter>table</parameter> <type>regclass</type>, > <parameter>policy_name</parameter> <type>name</type>, <optional> > <parameter>pretty</parameter> <type>boolean</type> </optional> ) > + <returnvalue>text</returnvalue> > + </para> > + <para> > + Reconstructs the <command>CREATE POLICY</command> statement from the > + system catalogs for a specified table and policy name. The result is a > + comprehensive <command>CREATE POLICY</command> statement. > + </para></entry> > + </row> > + </tbody> > > ( <parameter>table</parameter> <type>regclass</type> ... > this line is way too long, we can split it into several lines, it > won't affect the appearance. > > like: > <function>pg_get_policy_ddl</function> > ( <parameter>table</parameter> <type>regclass</type>, > <parameter>policy_name</parameter> <type>name</type>, > <optional> <parameter>pretty</parameter> > <type>boolean</type> </optional> ) > <returnvalue>text</returnvalue> > > Also, the explanation does not mention that the default value of > pretty is false. > > index 2d946d6d9e9..a5e22374668 100644 > --- a/src/backend/catalog/system_functions.sql > +++ b/src/backend/catalog/system_functions.sql > @@ -657,6 +657,12 @@ LANGUAGE INTERNAL > STRICT VOLATILE PARALLEL UNSAFE > AS 'pg_replication_origin_session_setup'; > > +CREATE OR REPLACE FUNCTION > + pg_get_policy_ddl(tableID regclass, policyName name, pretty bool > DEFAULT false) > +RETURNS text > +LANGUAGE INTERNAL > +AS 'pg_get_policy_ddl'; > + > > The partial upper casing above has no effect; it's the same as > ``pg_get_policy_ddl(tableid regclass, policyname name, pretty bool > DEFAULT false)`` > Thanks for updating the patch. Just one nitpick below. + append_ddl_option(&buf, pretty, 4, "USING (%s)", + TextDatumGetCString(expr)); The expression string already contains the parentheses, so we can omit them here, as well as in the WITH CHECK clause. -- Regards, Japin Li ChengDu WenWu Information Technology Co., Ltd.