>
> I don't really see this as important enough to justify introducing a
> nonstandard syntax for it...
>
> regards, tom lane
Sorry to quote like this, it makes me feel like a real nerd. :)
This quote from the SQL standard (1999) has it:
8.3 <between predicate> Function Specify a range comparison. Format <between
predicate>::= <row value expression> [ NOT ] BETWEEN [ ASYMMETRIC | SYMMETRIC ]
<rowvalue expression> AND <row value expression> Syntax Rules 1) If neither SYMMETRIC nor ASYMMETRIC is
specified,then ASYMMETRIC is implicit. 2) Let X, Y, and Z be the first, second, and third <row value
expression>s, respectively. 3) "X NOT BETWEEN SYMMETRIC Y AND Z" is equivalent to "NOT ( X
BETWEENSYMMETRIC Y AND Z )". 4) "X BETWEEN SYMMETRIC Y AND Z" is equivalent to "((X BETWEEN ASYMMETRIC
YAND Z) OR (X BETWEEN ASYMMETRIC Z AND Y))". 5) "X NOT BETWEEN ASYMMETRIC Y AND Z" is equivalent to "NOT ( X
BETWEEN ASYMMETRIC Y AND Z )". 6) "X BETWEEN ASYMMETRIC Y AND Z" is equivalent to "X>=Y AND X<=Z".
AccessRules None. General Rules None. Conformance Rules 1) Without Feature
T461,"Symmetric <between predicate>", conforming SQL language shall not specify SYMMETRIC or
ASYMMETRIC. 2) Without Feature S024, "Enhanced structured types", no subfield of the declared type of a
<rowvalue expression> that is simply contained in a <between predicate> shall be of a structured
type.
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