Description of the illustration tz_offset.gif
TZ_OFFSET returns the time zone offset corresponding to the argument based on the date the statement is executed. You can enter a valid time zone name, a time zone offset from UTC (which simply returns itself), or the keyword
DBTIMEZONE. For a listing of valid values for
time_zone_name, query the
TZNAME column of the
V$TIMEZONE_NAMES dynamic performance view.
Timezone region names are needed by the daylight savings feature. The region names are stored in two time zone files. The default time zone file is a small file containing only the most common time zones to maximize performance. If your time zone is not in the default file, then you will not have daylight savings support until you provide a path to the complete (larger) file by way of the
ORA_TZFILE environment variable.