How to make week and day concur in LibreOffice Base?

[QuartoDie]

I am working on a split database in Libre Office Base Version: 5.4.5.1, on Linux Mint Sylvia.
I have a calendar in which I need the week numbers in the year and the day numbers.
UPDATE “NEWYEAR” SET “DAYNUM”= DAYOFWEEK (“Date”)
UPDATE “NEWYEAR” SET “Week” = WEEK (“Date”)

Now when I request the daynumbers (the number 1 is Sunday as the first day of the week. But when I request the week number as above, Sunday is the last day in the week.

How do I get these numbers to concur. I would prefer to have Sunday as the first day of the week in both cases if that is possible.

Thanks

[QuartoDie]

e.g. Sunday, January 21, 2018, is listed as last day in the 3rd week in the year, but as day number 1. On my Linux system date-time settings choosing either Sunday or Monday as the first day of the week will not make these Week and Day concur on which is effectively the first day.

[Ratslinger]

Hello,

Day of week is determined by the database you are using. Some can be set to whatever you want. In HSQLDB day of week starts with Sunday ( = 1). However, when dealing with WEEK, the day of week starts with Monday. This has nothing to do with the OS and how it may be set (however locale may come into play).

For some interesting insight into this, see the answer by chrisb (dated 2015-02-05) in this post → How do I change start of week in OpenOffice 4.1
Based upon that post & strictly upon using dates in 2018, here is a test done:

[Lupp]

I’m wondering again and again at things as they are. There were good reasons to devolp standards, and there are standards. ISO 8601 defines the monday to be the first day of any week, and week number 1 to be the first week of which more than 3 days are in the new (or next) year. Why does software not simply apply the negociated and approved standards?

ISO week date

As far as I know there is no second standard rightfully competing with ISO 8601.