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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alexey M Boltenkov <padrebolt@yandex.ru>
cc: "Voillequin, Jean-Marc" <Jean-Marc.Voillequin@moodys.com>,
        "David G. Johnston" <david.g.johnston@gmail.com>,
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Subject: Re: unique index with several columns
In-reply-to: <6699c0e9-e358-1fc2-7ce4-7a24d4bc419e@yandex.ru>
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Comments: In-reply-to Alexey M Boltenkov <padrebolt@yandex.ru>
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Alexey M Boltenkov <padrebolt@yandex.ru> writes:
> You need the new v15 feature:
> NULLS [NOT] DISTINCT

That won't replicate the behavior shown by the OP though.
In particular, not the weird inconsistency for all-null rows.

			regards, tom lane