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. Remember that interval internally is "N months plus X seconds" (where N is integral but X needn't be). To avoid losing information, a product datatype would have to look something like "N months-squared plus X months-seconds plus Y seconds-squared", which offers no intuition whatever about how to operate on it. I doubt there's even a unique way to define square-rooting this. Add on top the fact that we really need to change interval to be "M months plus N days plus X seconds" to solve the ever-popular daylight-savings-transition issues, and a product datatype would get out of hand altogether. When I said "mash it down to seconds first", I was speaking very literally... regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html