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Nulls Not Distinct in Unique Indexes secton - Mailing list pgsql-docs

From Kirk Parker
Subject Nulls Not Distinct in Unique Indexes secton
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Msg-id CANwZ8r=hCu6=w=JRER27t9DMwvVngD55DmkU+NX_AZSfkm1KNg@mail.gmail.com
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In response to The use "Postgres" in docs  (Daniel Gustafsson <daniel@yesql.se>)
Responses Re: Nulls Not Distinct in Unique Indexes secton  (Laurenz Albe <laurenz.albe@cybertec.at>)
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The Unique Indexes section (https://www.postgresql.org/docs/15/indexes-unique.html) does not mention the new NULLS [ NOT ] DISTINCT capability of indexes (https://www.postgresql.org/docs/15/sql-createindex.html), and it probably should.

Specifically, it has the exact wording from previous versions (emphasis added):

    When an index is declared unique, multiple table
    rows with equal indexed values are not allowed.
    *Null values are not considered equal*.

We should consider adding "unless the NULLS NOT DISTINCT clause is used when creating the index", or something to that effect.

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