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WEEK

Returns the week number for a given date.

Sample usage

WEEK(Date)

Syntax

The following syntax returns the week number from a Date value.

WEEK( date_expression )

The following syntax returns the week number from a compatibility mode Date value.

WEEK( X [, format_string ])

Parameters

  • date_expression - a Date & Time field or expression.
  • X - a field or expression that evaluates to Text, Number, or compatibility mode Date.
  • format_string- format for X. Optional if X is correctly configured as a semantic date field.

Format strings for compatibility mode dates

Supported date functions accept the following input formats if X is a Text field or expression, or compatibility mode Date:

  • BASIC: %Y/%m/%d-%H:%M:%S
  • DEFAULT_DASH: %Y-%m-%d [%H:%M:%S]
  • DEFAULT_SLASH: %Y/%m/%d [%H:%M:%S]
  • DEFAULT_DECIMAL: %Y%m%d [%H:%M:%S]
  • RFC_1123: for example, 2008年5月24日 20:09:47 GMT
  • RFC_3339: for example, 2008年05月24日T20:09:47Z
  • DECIMAL_DATE: same as DEFAULT_DECIMAL

Any valid strptime format is accepted.

Supported time functions accept the following input format if X is a Number field or expression:

  • SECONDS: seconds since Epoch
  • MILLIS: milliseconds since Epoch
  • MICROS: microseconds since Epoch
  • NANOS: nanoseconds since Epoch
  • JULIAN_DATE: days since Epoch

Examples

Example formula Input Output
WEEK(Date) Jan 1, 2019 1
WEEK(Date as Text, 'BASIC') 2019年01月01日-09:40:45 1
WEEK(Date as Number, 'SECONDS') 1561784874 26

WEEK(Date as lots of Numbers, 'MILLIS')

1562004058620 27

Notes

This function works with both compatibility mode dates and upgraded Date and Date & Time data types.

This function returns the week number since the start of year per the ISO 8601 standard.

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Last updated 2026年08月26日 UTC.