How to get current date and time?

`NOW()` returns the current date and time. `TODAY()` returns the current date only.

Both are evaluated when the view is refreshed rather than continuously, so a workbook left open does not tick over.

They are most often used in relative date logic — `DATEDIFF('day', [Order Date], TODAY())` for days elapsed, or a boolean like `[Order Date] >= DATEADD('month', -3, TODAY())` to flag the last quarter.

One thing worth knowing for an interview: with a live connection these usually resolve to the database server's clock, while an extract uses the machine refreshing it — which matters if your systems sit in different time zones.