# ISO 8601 with Microseconds Key: `datetime.timestamp.iso_8601_microseconds` Extended ISO 8601 with microsecond precision and UTC indicator. Common in high-precision logging and scientific data. Page: Format: `%Y-%m-%dT%H:%M:%S.%fZ` Samples: `2024-01-15T10:30:00.123456Z`, `2019-12-31T23:59:59.000000Z` ## Use it Shell ```shell finetype infer -i '2024-01-15T10:30:00.123456Z' --mode column # → datetime.timestamp.iso_8601_microseconds ``` DuckDB ```sql SELECT ft_infer('2024-01-15T10:30:00.123456Z'); -- → 'datetime.timestamp.iso_8601_microseconds' ``` Cast template: {col} is your column ```sql strptime({col}, '%Y-%m-%dT%H:%M:%S.%fZ') -- Format: %Y-%m-%dT%H:%M:%S.%fZ ``` ## Background ### Origin ISO 8601 is maintained by the International Organization for Standardization, which first released it in 1988.[[1]](https://en.wikipedia.org/wiki/ISO_8601) ISO 8601-1:2019 represents slightly updated contents of the previous ISO 8601:2004 standard.[[1]](https://en.wikipedia.org/wiki/ISO_8601) In ISO 8601, a combined date and time representation uses the letter T as the delimiter between the date and the time.[[1]](https://en.wikipedia.org/wiki/ISO_8601) ISO 8601 allows a decimal fraction to be added to the lowest order time element of a time representation.[[1]](https://en.wikipedia.org/wiki/ISO_8601) ISO 8601 sets no limit on the number of decimal places, which needs to be agreed to by the communicating parties.[[1]](https://en.wikipedia.org/wiki/ISO_8601) ISO 8601 marks a time in UTC by adding a Z directly after the time, without a space.[[1]](https://en.wikipedia.org/wiki/ISO_8601) RFC 3339, Date and Time on the Internet: Timestamps, was written by G. Klyne and C. Newman and published in July 2002.[[2]](https://www.rfc-editor.org/rfc/rfc3339) RFC 3339 describes itself as a profile of the ISO 8601 standard for representation of dates and times using the Gregorian calendar.[[2]](https://www.rfc-editor.org/rfc/rfc3339) RFC 3339's grammar defines the fraction of a second, time-secfrac, as a full stop followed by one or more digits.[[2]](https://www.rfc-editor.org/rfc/rfc3339) RFC 3339 calls fractions of a second the one rarely used option in its format.[[2]](https://www.rfc-editor.org/rfc/rfc3339) RFC 3339 allows the T and Z characters to be written in lower case as t and z.[[2]](https://www.rfc-editor.org/rfc/rfc3339) ### Use Kubernetes defines a MicroTime type, described in its source as a version of Time with microsecond level precision.[[3]](https://raw.githubusercontent.com/kubernetes/apimachinery/master/pkg/apis/meta/v1/micro_time.go) Kubernetes' RFC3339Micro layout is 2006-01-02T15:04:05.000000Z07:00.[[3]](https://raw.githubusercontent.com/kubernetes/apimachinery/master/pkg/apis/meta/v1/micro_time.go) Kubernetes MicroTime values are converted to UTC before being formatted with the RFC3339Micro layout for JSON.[[3]](https://raw.githubusercontent.com/kubernetes/apimachinery/master/pkg/apis/meta/v1/micro_time.go) In Go's time package, a decimal point followed by zeros in a layout prints a fractional second to the given number of decimal places.[[4]](https://pkg.go.dev/time) In Go's time package, a decimal point followed by nines in a layout prints a fractional second with trailing zeros removed.[[4]](https://pkg.go.dev/time) Go's RFC3339Nano layout is 2006-01-02T15:04:05.999999999Z07:00.[[4]](https://pkg.go.dev/time) Go's time package prints Z instead of an offset for the UTC zone when the sign in the layout is replaced with a Z.[[4]](https://pkg.go.dev/time) Python's strftime directive %f writes the microsecond as a decimal number zero-padded to 6 digits.[[5]](https://docs.python.org/3/library/datetime.html) When used with Python's strptime, the %f directive accepts from one to six digits and zero pads on the right.[[5]](https://docs.python.org/3/library/datetime.html) Python's datetime.isoformat omits the fractional part when the microsecond is 0, unless a timespec such as microseconds is given.[[5]](https://docs.python.org/3/library/datetime.html) Python's datetime.isoformat writes a UTC datetime with the offset +00:00 rather than Z, as in the documentation's example 2019-05-18T15:17:00+00:00.[[5]](https://docs.python.org/3/library/datetime.html) The timezone of JavaScript's toISOString output is always UTC, as denoted by the suffix Z.[[6]](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString) PostgreSQL's timestamp types have a resolution of 1 microsecond.[[7]](https://www.postgresql.org/docs/current/datatype-datetime.html) PostgreSQL accepts the uppercase T between date and time on input, but uses a space rather than T on output.[[7]](https://www.postgresql.org/docs/current/datatype-datetime.html) In a value determined to be timestamp without time zone, PostgreSQL silently ignores any time zone indication.[[7]](https://www.postgresql.org/docs/current/datatype-datetime.html) Load these values into a time-zone-aware column, or parse the Z explicitly, so that the UTC marker is not quietly thrown away. (Meridian's view) Before loading, check whether the six digits carry real precision or are padding, since a column of .000000 fractions says less about timing than its width suggests. (Meridian's view) ## Sources 1. [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) — secondary source 2. [RFC 3339: Date and Time on the Internet: Timestamps](https://www.rfc-editor.org/rfc/rfc3339) — standard 3. [micro\_time.go](https://raw.githubusercontent.com/kubernetes/apimachinery/master/pkg/apis/meta/v1/micro_time.go) — documentation 4. [time package - time - Go Packages](https://pkg.go.dev/time) — documentation 5. [datetime — Basic date and time types](https://docs.python.org/3/library/datetime.html) — documentation 6. [Date.prototype.toISOString() - JavaScript \| MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString) — documentation 7. [PostgreSQL: Documentation: 18: 8.5. Date/Time Types](https://www.postgresql.org/docs/current/datatype-datetime.html) — documentation