"Milen A. Radev" <[EMAIL PROTECTED]> writes: > Milorad Poluga напиÑа: >>> SELECT '10 years 1 mons 1 days'::interval - '9 years 10 mons 15 >>> days'::interval >>> ?column? >>> --------------- >>> 3 mons -14 days >>> >>> Why not '2 mons 16 days' ?
> Please read the last paragraph in section 8.5.1.4 of the manual > (http://www.postgresql.org/docs/8.1/static/datatype-datetime.html#AEN4775) > . It mentions the functions named "justify_days" and "justify_hours" > that could do what you need. justify_days doesn't currently do anything with this result --- it thinks its charter is only to reduce day components that are >= 30 days. However, I think a good case could be made that it should normalize negative days too; that is, the invariant on its result should be 0 <= days < 30, not merely days < 30. Similarly for justify_hours. Comments anyone? Patch anyone? regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
