In addition to the fact that rowids can change as mentioned above by mike and tom, recid and rowid values are not nearly as unique as you might have been led to believe (and the documentation does not say much about it). long ago, in a galaxy far away, a 32-bit recid was always unique within a database. that has not been true since 1998. to be specific

rows in two different tables can have the same rowid values.

rows residing in different partitions of a single table can have the same rowid value.

rows belonging to different tenants in the same multitenant table can have the same rowid value.