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Message-ID: <114fe468-204a-43a9-8edc-26ffd6d598a4@aklaver.com>
Date: Tue, 17 Mar 2026 13:19:49 -0700
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Subject: Re: Trying to understand pg_get_expr()
To: Marcos Pegoraro <marcos@f10.com.br>
Cc: pgsql-general <pgsql-general@postgresql.org>
References: <ddb9b483-d1fc-4380-84ce-fff20e35893e@aklaver.com>
 <CAB-JLwZdyUfnC047MzV9woskWH2dToNJEudR34AD8WprEn8Cig@mail.gmail.com>
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From: Adrian Klaver <adrian.klaver@aklaver.com>
In-Reply-To: <CAB-JLwZdyUfnC047MzV9woskWH2dToNJEudR34AD8WprEn8Cig@mail.gmail.com>
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On 3/17/26 1:08 PM, Marcos Pegoraro wrote:
> Em ter., 17 de mar. de 2026 às 16:31, Adrian Klaver 
> <adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>> escreveu:
> 
>     Why does the = 'test' not return anything?
> 
> 
> for me pg_get_expr(adbin, adrelid) returns 'test'::character varying
> so it differs from 'test'

I should have indicated I tried casting:

SELECT
     adrelid::regclass,
     pg_typeof(pg_get_expr(adbin, adrelid)),
     pg_get_expr(adbin, adrelid)
FROM
     pg_attrdef
WHERE
     adrelid = 'default_test'::regclass
     AND pg_get_expr(adbin, 0) = 'test'::character varying;

  adrelid | pg_typeof | pg_get_expr
---------+-----------+-------------

I also tried other combinations of casting both sides of "=" and it 
still did not work.


> 
> regards
> Marcos


-- 
Adrian Klaver
adrian.klaver@aklaver.com