From Xojo Documentation
| This item was deprecated in version 2019r2.
Please use RowSet.BeforeFirstRow as a replacement.
Returns True when the RecordSet is before the first row or the RecordSet is empty.
A new RecordSet is always at the first row (if any rows were returned). The only way to set the RecordSet to be before the first row is to use RecordSet.MovePrevious, which is not supported by all data sources.
This moves the RecordSet pointer so that BOF is True:
rs = db.SQLSelect("SELECT * FROM data")
If rs <> Nil Then
If rs.BOF Then MsgBox("BOF!")