Daylight Saving Time
A practice in many regions of advancing clocks by one hour in spring and summer to conserve energy. For scheduled task systems, the day of a daylight saving transition has 23 or 25 hours, and certain local times either do not exist or occur twice, making it an edge case that scheduling must handle.
Timeline (last 90 days)
Every year at 2:00 a.m. on the last Sunday of March, clocks are moved forward 1 hour into daylight saving time; at 3:00 a.m. on the last Sunday of October, they are moved back 1 hour to standard time.
Daylight saving time switches mean that two days each year are not 24 hours but 23 or 25 hours; certain local times do not exist or occur twice on the switch day.
The spring-forward daylight saving time transition causes one hour of local time to not exist; a scheduled payment task triggered during this period may enter an infinite loop, throw an exception, or skip the transaction.
The autumn fall-back daylight saving time transition causes the same hour to occur twice; if a ledger relies on local timestamps for daily uniqueness constraints, it can result in primary key conflicts, duplicate charges, or rejection of valid transactions.
All Facts (4)
Every year at 2:00 a.m. on the last Sunday of March, clocks are moved forward 1 hour into daylight saving time; at 3:00 a.m. on the last Sunday of October, they are moved back 1 hour to standard time.
50%UnverifiedDaylight saving time switches mean that two days each year are not 24 hours but 23 or 25 hours; certain local times do not exist or occur twice on the switch day.
50%UnverifiedThe spring-forward daylight saving time transition causes one hour of local time to not exist; a scheduled payment task triggered during this period may enter an infinite loop, throw an exception, or skip the transaction.
50%UnverifiedThe autumn fall-back daylight saving time transition causes the same hour to occur twice; if a ledger relies on local timestamps for daily uniqueness constraints, it can result in primary key conflicts, duplicate charges, or rejection of valid transactions.
50%