Re: [HACKERS] Interval subtracting - Mailing list pgsql-sql

From Markus Schaber
Subject Re: [HACKERS] Interval subtracting
Date
Msg-id 440EC8FF.9080201@logix-tt.com
Whole thread Raw
In response to Re: [HACKERS] Interval subtracting  (Scott Marlowe <smarlowe@g2switchworks.com>)
Responses Re: [HACKERS] Interval subtracting
List pgsql-sql
Hi, Scott,

Scott Marlowe wrote:

>>But it isn't '-2 months, -1 day'.  I think what you are saying is what I
>>am saying, that we should make the signs consistent.
> Pretty much.  It just seems wrong to have different signs in what is
> essentially a single unit.
> 
> We don't say 42 degrees, -12 minutes when measuring arc, do we?  Then
> again, maybe some folks do.  It just seems wrong to me.

But we say "quarter to twelve", at least in some areas on this planet.

The problem is that months have different lengths. '2 months - 1 day'
can be '1 month 27 days', '1 month 28 days', '1 month 29 days' or '1
month 30 days', depending on the timestamp we apply the interval.

Markus
-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

Fight against software patents in EU! www.ffii.org www.nosoftwarepatents.org


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