Kind people,
I just ran across this, and was wondering whether it's worth a
back-patch. The interval type has an aggregate for average (AVG), but
not one for standard deviation (STDDEV) or variance (VARIANCE).
Is this a bug? Is there some problem with defining variance over
intervals?
TIA for
David Fetter wrote:
I just ran across this, and was wondering whether it's worth a
back-patch.
New features are not back-patched.
The interval type has an aggregate for average (AVG),
but not one for standard deviation (STDDEV) or variance (VARIANCE).
Is this a bug?
No, it's a missing
David Fetter [EMAIL PROTECTED] writes:
I just ran across this, and was wondering whether it's worth a
back-patch. The interval type has an aggregate for average (AVG), but
not one for standard deviation (STDDEV) or variance (VARIANCE).
AFAICS, stddev/variance require the concept of
Tom Lane wrote:
AFAICS, stddev/variance require the concept of multiplying two input
values together (square, and also square root, are in the formulas).
I don't know what it means to multiply two intervals --- there's no
such operator in Postgres, anyway.
The problem is not much different
Peter Eisentraut [EMAIL PROTECTED] writes:
The problem is that an interval datum already implies the units, so in
order to allow interval * interval we would have to add a new type
interval squared, which would probably be considered to be a bit
foolish.
Not only foolish but complicated.
On Mon, Jul 12, 2004 at 11:10:34AM -0400, Tom Lane wrote:
Peter Eisentraut [EMAIL PROTECTED] writes:
The problem is that an interval datum already implies the units,
so in order to allow interval * interval we would have to add a
new type interval squared, which would probably be considered