relationship between two datetime columns

Hi fisqkuz1 ,

According to your screenshots, it seems that you have highlighted the mtuCetStart column from Table1 and weekDayCet column from Table2,  but they are not like you mentioned ——They are both date/time in power query.

So do you mean mtuCetEnd or mtuCetStart column from Table2? Based on my test, the default relationship would be one-one,which is the most suitable.But certainly you could change it to one-many.

In additional, I saw mtuID and mtuCetStart column in both tables, therefore I'd suggest you created relationships based on these fields which is meaningful.

Best Regards,
Eyelyn Qin
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