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CIF Date and Time

Many CIF data items take as value a date or a date and time (e.g. _audit_creation_date) or may include a date/time string as part of their expected content (e.g. _audit_update_record). The convention for expressing a date/time string is as follows, and is consistent with the ISO standard ISO 8601:1988(E). A unique instant in time may be defined by concatenating

a date string in the format YYYY-MM-DD, where YYYY represents the year number in the Occidental Gregorian calendar, MM is the (zero-padded) month number, and DD is the (zero-padded) day number

and optionally

the character "T" followed by a time in the 24-hour clock format hh:mm:ss, where hh, mm and ss are respectively the hour, minute and second, zero-padded as necessary
a plus or minus character, corresponding to time zone offsets respectively east and west of Greenwich, followed by the offset value in the format hh:mm (representing hours and minutes difference from Coordinated Universal Time)

Depending on the required precision of the date/time, the full string may be truncated from the right as appropriate.

Examples

1997-08-12T13:55:58-05:00: Four minutes and two seconds before two o'clock on the afternoon of 12 August 1997, at the latitude of Hamilton, Ontario (corresponding to supper time at Greenwich).
1997-08-12T13:55:58+05:45: Four minutes and two seconds before two o'clock on the afternoon of 12 August 1997, at the latitude of Kathmandu, Nepal
1997-08-12T13:55:58: Four minutes and two seconds before two o'clock on the afternoon of 12 August 1997, local time
1997-08-12T13:55: Five minutes to two, afternoon of 12 August 1997
1997-08-12: 12 August 1997

Updated 12 August 1997

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