Created
October 15, 2020 15:10
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Postgresql logical implication operator
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CREATE FUNCTION | |
logical_implication(a boolean, b boolean) | |
RETURNS | |
boolean | |
LANGUAGE | |
sql | |
IMMUTABLE | |
PARALLEL SAFE | |
RETURNS NULL ON NULL INPUT | |
COST 1 | |
AS $$ | |
SELECT NOT a OR b | |
$$ | |
; | |
CREATE OPERATOR -> | |
( function = logical_implication | |
, leftarg = boolean | |
, rightarg = boolean | |
) | |
; |
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Not checked the boolean table for that one yet, still I think that
OR NOT
is "hard" on the human mind in regular SQL, especially as the human than had to triple check precedence rules. I'd still prefer the operator.