From: Tom Lane <tgl@sss.pgh.pa.us>
To: jian he <jian.universality@gmail.com>
cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: bug when apply fast default mechanism for adding new column over
 domain with default value
In-reply-to: <3664075.1741018726@sss.pgh.pa.us>
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Mon, 03 Mar 2025 11:18:46 -0500"
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Date: Mon, 03 Mar 2025 13:38:38 -0500
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I wrote:
> jian he <jian.universality@gmail.com> writes:
>> within ATExecAddColumn, we can
>>     if (!missingIsNull)
>>         StoreAttrMissingVal(rel, attribute->attnum, missingval, missing=
IsNull);
>> to save some cycles?

> Probably not really worth it: surely that's going to be a very
> infrequent edge case.

On second thought, it is worth doing like that, not on speed
grounds but because we can make StoreAttrMissingVal simpler
by not handling the is-null case at all.

Pushed with that adjustment and some other minor polishing.

			regards, tom lane