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Date: Sun, 19 Apr 2026 17:53:21 -0700
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Subject: Re: List of encodings
To: Igor Korot <ikorot01@gmail.com>
Cc: "David G. Johnston" <david.g.johnston@gmail.com>,
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From: Adrian Klaver <adrian.klaver@aklaver.com>
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On 4/19/26 5:19 PM, Igor Korot wrote:
> Hi, Adrian,
> 
> On Sun, Apr 19, 2026 at 4:21 PM Adrian Klaver <adrian.klaver@aklaver.com> wrote:

>>> What I noticed is that all encodings are default, as they all have 't'
>>> in the last column.
>>>
>>> It's a little confusing...
>>
>> Not if you read the docs:
>>
>> https://www.postgresql.org/docs/current/catalog-pg-conversion.html
>>
>> "The catalog pg_conversion describes encoding conversion functions. See
>> CREATE CONVERSION for more information."
>>
>> https://www.postgresql.org/docs/current/sql-createconversion.html
>>
>> "Conversions that are marked DEFAULT can be used for automatic encoding
>> conversion between client and server. To support that usage, two
>> conversions, from encoding A to B and from encoding B to A, must be
>> defined."
> 
>  From the https://www.postgresql.org/docs/current/catalog-pg-conversion.html:
> 
> [quote]
> 
> condefault bool
> 
> True if this is the default conversion
> [/quote]
> 
> So, what info do I trust?

Both.

In your setup all the installed encoding conversion functions are also 
the default for those conversions. It is possible to create/install a 
conversion function that is not the default.

> 
> Thank you.
> 


-- 
Adrian Klaver
adrian.klaver@aklaver.com