Date Dimension Explorer

Change the logical execution date ("Today") and observe how helper attributes like IsCurrentDay and IsCurrentMonth break the static, append-only promise of the date dimension by forcing updates to historical rows.

System Date (Today): -

DateKey	FullDate	DayOfWeek	IsCurrentDay	IsCurrentMonth	FiscalYear

Select a control above.

When Today changes, the database must run an UPDATE statement to reset the old current day/month flags to false and set the new ones to true. In a data lakehouse, mutating rows triggers rewriting of parquet files and causes downstream caches to serve stale, inconsistent temporal values.