On 2003-03-31 10:48:05 +0200, Peter Conrad wrote: > Certain java.sql.Timestamp values aren't written to (or retrieved from) > the database correctly. Timestamps affected are in the time interval just > before switchover from DST to non-DST (the bug was noticed on > October 27th 2002 for the first time, when the switchover from MET/DST to MET > took place). Various timestamp values in the range > 2:00 AM - 2:59:59 AM (MET/DST) on October 27th 2002 as well as on October > 26th 2003 have been verified to reproduce the bug, with the database as > well as the JDBC client running in MET. [...] > Timestamp problem = new Timestamp(1067130000000L); // 26.10.03 02:00 MET/DST That's a general problem with daylight savings time. On the switch from DST to standard time, one hour (02:00:00 .. 03:00:00 in the case of MET) occurs twice. If a timestamp is stored in the local timezone but without timezone information, this information is ambiguous. This is not Oracle-specific but would happen with any database which stores timestamps in "human readable" form without timezone information. If you need to store unambiguous timestamps, use UTC or a numeric "units since the epoch" format (like POSIX time_t or Java millis). What's nasty about your sample code is that you specify the timestamp in Java millis, but it isn't stored that way. It is easy for a programmer to forget about the type conversion and possible loss of information. hp -- _ | Peter J. Holzer | Unser Universum wäre betrüblich |_|_) | Sysadmin WSR / LUGA | unbedeutend, hätte es nicht jeder | | | hjp@wsr.ac.at | Generation neue Probleme bereit. __/ | http://www.hjp.at/ | -- Seneca, naturales quaestiones
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