ROWID and UROWID

ROWID

The ROWID data type is used to store physical address of each row in the database. This data type is primarily for values returned by the ROWID pseudocolumn.

UROWID[(n)]

The UROWID data type is used to store the logical addresses of index-organized and foreign tables.

n is the size of a UROWID column. The range of n is 1 to 4000. The default value is 4000.

This data type is available in Oracle 9i Release 1 (9.0.1) or later.