datefmt

Formats recognized date fields (19 formats recognized) to a specified date format using strftime date format specifiers.

Table of Contents | Source: src/cmd/datefmt.rs | 📇🚀👆

Description | Examples | Usage | Arguments | Datefmt Options | Common Options

Description ↩

Formats recognized date fields (19 formats recognized) to a specified date format using strftime date format specifiers.

For recognized date formats, see https://github.com/dathere/qsv-dateparser?tab=readme-ov-file#accepted-date-formats

See https://docs.rs/chrono/latest/chrono/format/strftime/ for accepted date format specifiers for --formatstr. Defaults to ISO 8601/RFC 3339 format when --formatstr is not specified. ( "%Y-%m-%dT%H:%M:%S%z" - e.g. 2001-07-08T00:34:60.026490+09:30 )

Examples ↩

Format dates in Open Date column to ISO 8601/RFC 3339 format:

qsv datefmt 'Open Date' file.csv

Format multiple date columns in file.csv to ISO 8601/RFC 3339 format:

qsv datefmt 'Open Date,Modified Date,Closed Date' file.csv

Format all columns that end with "_date" case-insensitive in file.csv to ISO 8601/RFC 3339 format:

qsv datefmt '/(?i)_date$/' file.csv

Format dates in OpenDate column using '%Y-%m-%d' format:

qsv datefmt OpenDate --formatstr '%Y-%m-%d' file.csv

Format multiple date columns using '%Y-%m-%d' format:

qsv datefmt OpenDate,CloseDate,ReopenDate --formatstr '%Y-%m-%d' file.csv

Get the week number for OpenDate and store it in the week_number column:

qsv datefmt OpenDate --formatstr '%V' --new-column week_number file.csv

Get the day of the week for several date columns and store it in the corresponding weekday columns:

qsv datefmt OpenDate,CloseDate --formatstr '%u' --rename Open_weekday,Close_weekday file.csv

For more examples, see tests.

See also https://github.com/dathere/qsv/wiki/Transform-and-Reshape#datefmt

Usage ↩

qsv datefmt [--formatstr=<string>] [options] <column> [<input>]
qsv datefmt --help

Arguments ↩

Argument	Description
<column>	The column/s to apply the date formats to. Note that the argument supports multiple columns. See 'qsv select --help' for the format details.
<input>	The input file to read from. If not specified, reads from stdin.

Datefmt Options ↩

Option	Type	Description	Default
‑c, ‑‑new‑column	string	Put the transformed values in new column(s) instead of replacing the source column(s). When the selection has multiple columns, pass a comma-separated list of new column names that match the selection count (e.g. --new-column 'open_iso,close_iso' for 'OpenDate,CloseDate'). To rename in place instead, use --rename.
‑r, ‑‑rename	string	New name for the transformed column.
‑‑prefer‑dmy	flag	Prefer to parse dates in dmy format. Otherwise, use mdy format.
‑‑keep‑zero‑time	flag	If a formatted date ends with "T00:00:00+00:00", keep the time instead of removing it.
‑‑input‑tz=<string>	string	The timezone to use for the input date if the date does not have timezone specified. The timezone must be a valid IANA timezone name or the string "local" for the local timezone. See https://en.wikipedia.org/wiki/List_of_tz_database_time_zones for a list of valid timezone names.	UTC
‑‑output‑tz=<string>	string	The timezone to use for the output date. The timezone must be a valid IANA timezone name or the string "local".	UTC
‑‑default‑tz=<string>	string	Fallback timezone consulted only when --input-tz or --output-tz is set to "local" but local-timezone detection fails. Defaults to UTC. Does NOT override the --input-tz / --output-tz defaults — use --utc to force both input and output to UTC. The timezone must be a valid IANA timezone name or the string "local".
‑‑utc	flag	Shortcut for --input-tz and --output-tz set to UTC.
‑‑zulu	flag	Shortcut for --output-tz set to UTC and --formatstr set to "%Y-%m-%dT%H:%M:%SZ".
‑R, ‑‑ts‑resolution	string	The resolution to use when parsing Unix timestamps. Valid values are "sec", "milli", "micro", "nano".	sec
‑j, ‑‑jobs	integer	The number of jobs to run in parallel. When not set, the number of jobs is set to the number of CPUs detected.
‑b, ‑‑batch	integer	The number of rows per batch to load into memory, before running in parallel. Automatically determined for CSV files with more than 50000 rows. Set to 0 to load all rows in one batch. Set to 1 to force batch optimization even for files with less than 50000 rows.	50000

Common Options ↩

Option	Type	Description	Default
‑h, ‑‑help	flag	Display this message
‑o, ‑‑output	string	Write output to instead of stdout.
‑n, ‑‑no‑headers	flag	When set, the first row will not be interpreted as headers.
‑d, ‑‑delimiter	string	The field delimiter for reading CSV data. Must be a single character. (default: ,)
‑p, ‑‑progressbar	flag	Show progress bars. Not valid for stdin.

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Source: src/cmd/datefmt.rs | Table of Contents | README