This function returns
a value corresponding to a timestamp of the first millisecond of the
first day of the calendar week containing date.
The default output format is the DateFormat set in the script.
The weekstart() function determines which week the date falls into. It then returns a timestamp, in date format, for the first millisecond of that week. The first day of the week is determined by the FirstWeekDay environment variable. However, this can be superseded by the first_week_day argument in the weekstart() function.
Arguments
Argument
Description
timestamp
The date or timestamp to evaluate.
period_no
shift is an integer, where the value
0 indicates the week which contains date.
Negative values in shift indicate preceding weeks and positive values
indicate succeeding weeks.
first_week_day
Specifies the day on which the week starts. If omitted, the value of variable FirstWeekDay is used.
The possible values first_week_day are 0 for Monday, 1 for Tuesday, 2 for Wednesday, 3 for Thursday, 4 for Friday, 5 for Saturday, and 6 for Sunday.
For more information about the system variable, see FirstWeekDay.
When to use it
The weekstart() function is commonly used as part of an expression when the user would like the calculation to use the fraction of the week that has elapsed thus far. For example, it could be used if a user would like to calculate the total wages earned by employees in the week so far.
The following examples assume:
SET FirstWeekDay=0;
Function examples
Example
Result
weekstart('01/12/2013')
Returns 01/07/2013.
weekstart('01/12/2013', -1 )
Returns 11/31/2012.
weekstart('01/12/2013', 0, 1)
Returns
01/08/2013.
Regional settings
Unless otherwise specified, the examples in this topic use the following date format: MM/DD/YYYY. The date format is specified in the SET DateFormat statement in your data load script. The default date formatting may be different in your system, due to your regional settings and other factors. You can change the formats in the examples below to suit your requirements. Or you can change the formats in your load script to match these examples. For more information, see Modifying regional settings for apps and scripts.
Default regional settings in apps are based on the user profile. These regional format settings are not related to the language displayed in the Qlik Cloud user interface. Qlik Cloud will be displayed in the same language as the browser you are using.
If you want ISO settings for weeks and week numbers, make sure to have the following in the script:
Set DateFormat ='YYYY-MM-DD';
Set FirstWeekDay =0; // Monday as first week day
Set BrokenWeeks =0; //(use unbroken weeks)
Set ReferenceDay =4; // Jan 4th is always in week 1
If you want US settings, make sure to have the following in the script:
Set DateFormat ='M/D/YYYY';
Set FirstWeekDay =6; // Sunday as first week day
Set BrokenWeeks =1; //(use broken weeks)
Set ReferenceDay =1; // Jan 1st is always in week 1
The examples above results in the following from the weekstart() function:
Example of Weekstart function
Date
ISO week start
US week start
Sat 2020 Dec 26
2020-12-21
12/20/2020
Sun 2020 Dec 27
2020-12-21
12/27/2020
Mon 2020 Dec 28
2020-12-28
12/27/2020
Tue 2020 Dec 29
2020-12-28
12/27/2020
Wed 2020 Dec 30
2020-12-28
12/27/2020
Thu 2020 Dec 31
2020-12-28
12/27/2020
Fri 2021 Jan 1
2020-12-28
12/27/2020
Sat 2021 Jan 2
2020-12-28
12/27/2020
Sun 2021 Jan 3
2020-12-28
1/3/2021
Mon 2021 Jan 4
2021-01-04
1/3/2021
Tue 2021 Jan 5
2021-01-04
1/3/2021
Information noteThe week starts are on Mondays in the ISO column, and on Sundays in the US column.
Example 1 – No additional arguments
Overview
Open the Data load editor and add the load script below to a new tab.
The load script contains:
A dataset containing a set of transactions for 2022, which is loaded into a table called Transactions.
The date field provided in the DateFormat system variable (MM/DD/YYYY) format.
The creation of a field, start_of_week, that returns a timestamp for the start of the week when the transactions took place.
Load the data and open a sheet. Create a new table and add these fields as dimensions:
date
start_of_week
start_of_week_timestamp
Results table
date
start_of_week
start_of_week_timestamp
1/7/2022
01/02/2022
1/2/2022 12:00:00 AM
1/19/2022
01/16/2022
1/16/2022 12:00:00 AM
2/5/2022
01/30/2022
1/30/2022 12:00:00 AM
2/28/2022
02/27/2022
2/27/2022 12:00:00 AM
3/16/2022
03/13/2022
3/13/2022 12:00:00 AM
4/1/2022
03/27/2022
3/27/2022 12:00:00 AM
5/7/2022
05/01/2022
5/1/2022 12:00:00 AM
5/16/2022
05/15/2022
5/15/2022 12:00:00 AM
6/15/2022
06/12/2022
6/12/2022 12:00:00 AM
6/26/2022
06/26/2022
6/26/2022 12:00:00 AM
7/9/2022
07/03/2022
7/3/2022 12:00:00 AM
7/22/2022
07/17/2022
7/17/2022 12:00:00 AM
7/23/2022
07/17/2022
7/17/2022 12:00:00 AM
7/27/2022
07/24/2022
7/24/2022 12:00:00 AM
8/2/2022
07/31/2022
7/31/2022 12:00:00 AM
8/8/2022
08/07/2022
8/7/2022 12:00:00 AM
8/19/2022
08/14/2022
8/14/2022 12:00:00 AM
9/26/2022
09/25/2022
9/25/2022 12:00:00 AM
10/14/2022
10/09/2022
10/9/2022 12:00:00 AM
10/29/2022
10/23/2022
10/23/2022 12:00:00 AM
The start_of_week field is created in the preceding load statement by using the weekstart() function and passing the date field as the function’s argument.
The weekstart() function initially identifies which week the date value falls into, returning a timestamp for the first millisecond of that week.
Transaction 8191 took place on February 5. The FirstWeekDay system variable sets the first day of the week to a Sunday. The weekstart() function identifies that the first Sunday before February 5 – and therefore the start of the week – was on January 30, Therefore, the start_of_week value for that transaction returns the first millisecond of that day, which is January 30 at 12:00:00 AM.
Example 2 – period_no
Overview
Open the Data load editor and add the load script below to a new tab.
The load script contains:
The same dataset and scenario as the first example.
The creation of a field, previous_week_start, that returns the timestamp for the start of the quarter before the transaction took place.
Load the data and open a sheet. Create a new table and add these fields as dimensions:
date
previous_week_start
previous_week_start_timestamp
Results table
date
previous_week_start
previous_week_start_timestamp
1/7/2022
12/26/2021
12/26/2021 12:00:00 AM
1/19/2022
01/09/2022
1/9/2022 12:00:00 AM
2/5/2022
01/23/2022
1/23/2022 12:00:00 AM
2/28/2022
02/20/2022
2/20/2022 12:00:00 AM
3/16/2022
03/06/2022
3/6/2022 12:00:00 AM
4/1/2022
03/20/2022
3/20/2022 12:00:00 AM
5/7/2022
04/24/2022
4/24/2022 12:00:00 AM
5/16/2022
05/08/2022
5/8/2022 12:00:00 AM
6/15/2022
06/05/2022
6/5/2022 12:00:00 AM
6/26/2022
06/19/2022
6/19/2022 12:00:00 AM
7/9/2022
06/26/2022
6/26/2022 12:00:00 AM
7/22/2022
07/10/2022
7/10/2022 12:00:00 AM
7/23/2022
07/10/2022
7/10/2022 12:00:00 AM
7/27/2022
07/17/2022
7/17/2022 12:00:00 AM
8/2/2022
07/24/2022
7/24/2022 12:00:00 AM
8/8/2022
07/31/2022
7/31/2022 12:00:00 AM
8/19/2022
08/07/2022
8/7/2022 12:00:00 AM
9/26/2022
09/18/2022
9/18/2022 12:00:00 AM
10/14/2022
10/02/2022
10/2/2022 12:00:00 AM
10/29/2022
10/16/2022
10/16/2022 12:00:00 AM
In this instance, because a period_no of -1 was used as the offset argument in the weekstart() function, the function first identifies the week that the transactions take place in. It then looks one week prior and identifies the first millisecond of that week.
Transaction 8196 took place on June 15. The weekstart() function identifies that the week begins on June 12. Therefore, the previous week began on June 5 at 12:00:00 AM; this is the value that is returned for the previous_week_start field.
The load script contains the same dataset and scenario as the first example. However, in this example, we need to set Tuesday as the first day of the work week.
Load the data and open a sheet. Create a new table and add these fields as dimensions:
date
start_of_week
start_of_week_timestamp
Results table
date
start_of_week
start_of_week_timestamp
1/7/2022
01/04/2022
1/4/2022 12:00:00 AM
1/19/2022
01/18/2022
1/18/2022 12:00:00 AM
2/5/2022
02/01/2022
2/1/2022 12:00:00 AM
2/28/2022
02/22/2022
2/22/2022 12:00:00 AM
3/16/2022
03/15/2022
3/15/2022 12:00:00 AM
4/1/2022
03/29/2022
3/29/2022 12:00:00 AM
5/7/2022
05/03/2022
5/3/2022 12:00:00 AM
5/16/2022
05/10/2022
5/10/2022 12:00:00 AM
6/15/2022
06/14/2022
6/14/2022 12:00:00 AM
6/26/2022
06/21/2022
6/21/2022 12:00:00 AM
7/9/2022
07/05/2022
7/5/2022 12:00:00 AM
7/22/2022
07/19/2022
7/19/2022 12:00:00 AM
7/23/2022
07/19/2022
7/19/2022 12:00:00 AM
7/27/2022
07/26/2022
7/26/2022 12:00:00 AM
8/2/2022
08/02/2022
8/2/2022 12:00:00 AM
8/8/2022
08/02/2022
8/2/2022 12:00:00 AM
8/19/2022
08/16/2022
8/16/2022 12:00:00 AM
9/26/2022
09/20/2022
9/20/2022 12:00:00 AM
10/14/2022
10/11/2022
10/11/2022 12:00:00 AM
10/29/2022
10/25/2022
10/25/2022 12:00:00 AM
In this instance, because the first_week_date argument of 1 is used in the weekstart() function, it sets the first day of the week to Tuesday.
Transaction 8191 took place on February 5. The weekstart() function identifies that the first Tuesday before the this date – and therefore the start of the week and value returned – was February 1 at 12:00:00 AM.
Example 4 – Chart object example
Overview
Open the Data load editor and add the load script below to a new tab.
The load script contains the same dataset and scenario as the first example.
However, in this example, the unchanged dataset is loaded into the application. The calculation that returns a timestamp for the start of the week when the transactions took place is created as a measure in a chart object of the application.
Load the data and open a sheet. Create a new table and add this field as a dimension: date.
To calculate the start of the week in which a transaction takes place, add the following measures:
=weekstart(date)
=timestamp(weekstart(date))
Results table
date
start_of_week
start_of_week_timestamp
1/7/2022
01/02/2022
1/2/2022 12:00:00 AM
1/19/2022
01/16/2022
1/16/2022 12:00:00 AM
2/5/2022
01/30/2022
1/30/2022 12:00:00 AM
2/28/2022
02/27/2022
2/27/2022 12:00:00 AM
3/16/2022
03/13/2022
3/13/2022 12:00:00 AM
4/1/2022
03/27/2022
3/27/2022 12:00:00 AM
5/7/2022
05/01/2022
5/1/2022 12:00:00 AM
5/16/2022
05/15/2022
5/15/2022 12:00:00 AM
6/15/2022
06/12/2022
6/12/2022 12:00:00 AM
6/26/2022
06/26/2022
6/26/2022 12:00:00 AM
7/9/2022
07/03/2022
7/3/2022 12:00:00 AM
7/22/2022
07/17/2022
7/17/2022 12:00:00 AM
7/23/2022
07/17/2022
7/17/2022 12:00:00 AM
7/27/2022
07/24/2022
7/24/2022 12:00:00 AM
8/2/2022
07/31/2022
7/31/2022 12:00:00 AM
8/8/2022
08/07/2022
8/7/2022 12:00:00 AM
8/19/2022
08/14/2022
8/14/2022 12:00:00 AM
9/26/2022
09/25/2022
9/25/2022 12:00:00 AM
10/14/2022
10/09/2022
10/9/2022 12:00:00 AM
10/29/2022
10/23/2022
10/23/2022 12:00:00 AM
The start_of_week measure is created in the chart object by using the weekstart() function and passing the date field as the function’s argument.
The weekstart() function initially identifies which week the date value falls into, returning a timestamp for the first millisecond of that week.
Transaction 8191 took place on February 5. The FirstWeekDay system variable sets the first day of the week to a Sunday. The weekstart() function identifies that the first Sunday before February 5 – and therefore the start of the week – was January 30. Therefore, the start_of_week value for that transaction returns the first millisecond of that day, which is January 30 at 12:00:00 AM.
Example 5 – Scenario
Overview
Open the Data load editor and add the load script below to a new tab.
The load script contains:
A dataset which is loaded into a table called Payroll.
Data consisting of employee IDs, employee names, and the daily wage earned by each employee.
Employees begin work on Monday and work six days per week. The FirstWeekDay system variable must not be modified.
The end user would like a chart object that displays, by employee ID and employee name, the wages earned in the week to date.
The weekstart() function, by using today’s date as its first argument and 0 as its third argument, sets Monday as the first day of the week and returns the start date of the current week. By subtracting that result from the current date, the expression then returns the number of days that have elapsed so far this week.
The condition then evaluates whether there have been more than six days this week. If so, the employee’s day_rate is multiplied by 6 days. Otherwise, the day_rate is multiplied by the number of days that have occurred so far this week.
Variable
A variable in Qlik Sense is a container storing a static value or a calculation, for example a numeric or alphanumeric value.
The term dataset is sometimes synonymous with table. It can refer to the original source table, the table after undergoing transformations, or the fact and dimension tables in a data mart.
It can also refer to a logical table, where there are several instance tables and views:
Current data
History, which holds previous versions of the table
A field contains values, loaded from a data source. At a basic level, a field corresponds to a column in a table. Fields are used to create dimensions and measures in visualizations.
A preceding load is a script construct that allows you to load from the following LOAD or SELECT statement without specifying that source. Preceding loads are often faster than resident loads.
The load script is a sequence of statements that defines what data to load and how to link the different loaded tables. It can be generated with the Data manager, or with the Data load editor, where it also can be viewed and edited.
A measure is a calculation base on one ore more aggregations. For example, the sum of sales is a single aggregation, while the sum of sales divided by the count of customers is a measure based on two aggregations.