WEEKDAY Function

Derives the numeric value for the day of the week (1, 2, etc.). Input must be a reference to a column containing Datetime values.

NOTE: If the source Datetime value does not include a valid input for this function, a missing value is returned.

Tip: You can use the DATEFORMAT function to generate text versions of the day of the week. See Examples below.

Wrangle vs. SQL: This function is part of Wrangle, a proprietary data transformation language. Wrangle is not SQL. For more information, see Wrangle Language.

Basic Usage

Column reference example:

weekday(MyDate)

Output: Returns the numeric weekday values derived from the MyDate column.

Syntax and Arguments

weekday(datetime_col)

ArgumentRequired?Data TypeDescription
datetime_colYdatetimeName of column whose weekday values are to be computed

For more information on syntax standards, see Language Documentation Syntax Notes.

datetime_col

Name of the column whose day-of-week value is to be computed.

  • Missing values for this function in the source data result in missing values in the output.
  • Multiple columns and wildcards are not supported.

Tip: You cannot insert constant Datetime values as inputs to this function. However, you can use the following: WEEKDAY(DATE(12,20,2017)) .

Usage Notes:

Required?Data TypeExample Value
YesDatetimemyDate

Examples

Tip: For additional examples, see How-to Guides.

Example - Day of Date functions

This example illustrates how you can apply functions to derive day-of-week values out of a column of Datetime type:

  • WEEKDAY - returns numeric value for the day of the week for source Datetime values. See WEEKDAY Function.
  • WEEKNUM - returns the numeric value for the week within the year for source Datetime values. See WEEKNUM Function.
  • DATEFORMAT - can be used to format Datetime values in many different ways. See DATEFORMAT Function.

Source:

myDate
10/30/17
10/31/17
11/1/17
11/2/17
11/3/17
11/4/17
11/5/17
11/6/17


Transformation:

The following transformation step generates a numeric value for the day of week in a new column:

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula WEEKDAY (myDate)
Parameter: New column name 'weekDayNum'

The following step generates a full text version of the name of the day of the week:

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula DATEFORMAT(myDate, 'EEEE')
Parameter: New column name 'weekDayNameFull'

The following step generates a three-letter abbreviation for the name of the day of the week:

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula DATEFORMAT(myDate, 'EEE')
Parameter: New column name 'weekDayNameShort'

The following step generates the numeric value of the week within the year:

Transformation Name New formula
Parameter: Formula type Single row formula
Parameter: Formula WEEKNUM (myDate)
Parameter: New column name 'weekNum'

Results:

myDateweekDayNumweekDayNameFullweekDayNameShortweekNum
10/30/171MondayMon44
10/31/172TuesdayTue44
11/1/173WednesdayWed44
11/2/174ThursdayThu44
11/3/175FridayFri44
11/4/176SaturdaySat44
11/5/177SundaySun45
11/6/171MondayMon45