[DB-SIG] Date/Time question

hme@informatik.uni-rostock.de hme@informatik.uni-rostock.de
Wed, 22 Mar 2000 14:25:05 +0100


Hello,

implementing my Ingres module, I run across the following
implementation aspects:  According to the DB API 2.0, there are methods
for building several time/date value combinations.  But the DATETIME
object seems to represent absolute values only.

Is this correct?  If so, has someone made a proposal for representing
time intervals.  Since Ingres supports arithmetic on absolute and
relative time, it would be nice to have both.

Most database systems, that support temporal data, have a notation of
`now' and `today', why these values not make default parameters?  As
far as I know some Systems internally represent date/time as strings
(Informix, Ingres).  Since there's no string parameter to the date/time
methods, conversion takes place two times.  Another side effect would
be, that `now' and `today' are evaluated at execution time, not at
PREPARE.

Peace

Holger

-- 
Holger Meyer, Uni of Rostock, Dpt. of CS, DB Research Group
hm@guug.de, http://www.informatik.uni-rostock.de/~hme/