# Help me write the constraints for day of week

**URL:** <https://forum.sambapos.com/t/help-me-write-the-constraints-for-day-of-week/16728>\
**Category:** V5 Question\
**Created:** [January 8, 2018, 4:53am UTC](https://forum.sambapos.com/t/help-me-write-the-constraints-for-day-of-week/16728 "2018-01-08T04:53:02Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![WingoLED](https://forum.sambapos.com/letter_avatar_proxy/v4/letter/w/6bbea6/32.png) [@WingoLED](https://forum.sambapos.com/u/WingoLED)\
**Post date:** [January 8, 2018, 4:53am UTC](https://forum.sambapos.com/t/help-me-write-the-constraints-for-day-of-week/16728/1 "2018-01-08T04:53:02Z")

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![image](https://forum.sambapos.com/uploads/default/original/3X/8/8/8813464c722e55d18e7e8e5d258408ce4ee17321.png)

or

you have any suggestion for a more elegant way to achieve beblow

 ![Day of Week Implementation Question 2](https://forum.sambapos.com/uploads/default/original/3X/9/4/94c5258bb4e7ff7ef6cd5518640c5ada445b3011.jpg)

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<div class="post-metadata">

**Author:** ![WingoLED](https://forum.sambapos.com/letter_avatar_proxy/v4/letter/w/6bbea6/32.png) [@WingoLED](https://forum.sambapos.com/u/WingoLED)\
**Post date:** [January 8, 2018, 5:20am UTC](https://forum.sambapos.com/t/help-me-write-the-constraints-for-day-of-week/16728/2 "2018-01-08T05:20:03Z")

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Solved it

Simply put the {DATE:ddd} in the COMMAND VALUE box solves the problem, no constraints needed. Just match the value to the Order Tags.

But anyway I would like to see some examples on how to write constraints using system variables and functions. Anyone can show me some?

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**Author:** ![JTRTech](https://forum.sambapos.com/user_avatar/forum.sambapos.com/jtrtech/32/21270_2.png) [@JTRTech](https://forum.sambapos.com/u/JTRTech)\
**Post date:** [January 8, 2018, 9:19am UTC](https://forum.sambapos.com/t/help-me-write-the-constraints-for-day-of-week/16728/3 "2018-01-08T09:19:20Z")

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Try looking at almost any tutorial…  
As example would be  
‘{DATE:ddd}’ == ‘Mon’