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Re: Building infrastructure for B-Tree deduplication that recognizes when opclass equality is also equivalence - Mailing list pgsql-hackers

From Andrew Gierth
Subject Re: Building infrastructure for B-Tree deduplication that recognizes when opclass equality is also equivalence
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Msg-id 87wodpkod2.fsf@news-spur.riddles.org.uk
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In response to Re: Building infrastructure for B-Tree deduplication that recognizes when opclass equality is also equivalence  (Antonin Houska <ah@cybertec.at>)
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>>>>> "Antonin" == Antonin Houska <ah@cybertec.at> writes:

 >> It is set to false for numeric and float4, float8.

 Antonin> Are you sure about these?

numeric values can compare equal but have different display scales (see
hash_numeric).

float4 and float8 both have representations for -0, which compares equal
to 0. (numeric technically has a representation for -0 too, but I
believe the current code carefully avoids ever generating it.)

-- 
Andrew (irc:RhodiumToad)

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