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Dates & Time Zones
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Dates & Time Zones
Time Zones and DST: IANA Names, Gaps and Overlaps
Why CST and IST are ambiguous, what 8 languages do with 02:30 on the DST spring-forward day, zdump transitions, and one instant two runtimes disagree on.
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Dates & Time Zones
Scheduling Across Time Zones: Cron, DST and Clock Skew
A 02:30 job ran 0 times in March and twice in October; a weekly meeting moved an hour; 30 s of skew failed half the tokens. Simulated, measured, fixed.
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Dates & Time Zones
Dates in Databases: SQLite TEXT vs INTEGER vs REAL
1M timestamps stored three ways in SQLite: file size, index speed, a mixed-offset sort that reverses order, MySQL DATETIME vs TIMESTAMP, Y2K38 in C, JSON.
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Dates & Time Zones
Unix Timestamps, UTC and ISO 8601 for Beginners
Instant vs wall-clock time, epoch seconds vs ms (the 1970 and year-58142 bugs), ISO 8601 and Python's naive vs aware TypeError, all run for real.
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Dates & Time Zones
Parsing and Formatting Dates: ISO 8601 and Locales
Date lecture 3: real runs of strptime, PHP createFromFormat turning Feb 30 into Mar 2, JS Date parsing by time zone, Java's YYYY bug and locale names.
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Dates & Time Zones
Date Arithmetic: Month Ends, Leap Years, DST Days
Date lecture 4: Jan 31 + 1 month in 7 tools (Feb 28 or Mar 3), Feb 29 + 1 year, a 23-hour day across DST, ages and business days, all from real runs.
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