Seems simple enough: The table, produced by your Power BI gen2 dataflow, contains a time column. You want to output this table to OneLake, then have Power BI read from it using a DirectLake-powered semantic model.

Sounds easy, but not so fast! When you try to set up the dataflow’s output mappings, columns of type time are not supported for OneLake destinations. Ouch!

So, what do you do?

Try leveraging the fact that Power BI’s time values are, behind the scenes, actually datetime values. For proper “type time” behavior, Power BI expects that the date part of each datetime value is set to Power BI’s epoch date (the date it considers day 0, which is 1899-12-30) and it also needs to know that the column is expected to have time behaviors.

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