ROWIDTONCHAR converts a rowid value to NVARCHAR2 data type. The result of this conversion is always in the national character set and is 18 characters long.
The following example converts a rowid value to an NVARCHAR2 string:
SELECT LENGTHB( ROWIDTONCHAR(ROWID) ) Length, ROWIDTONCHAR(ROWID)
FROM employees
ORDER BY length;
LENGTH ROWIDTONCHAR(ROWID
---------- ------------------
36 AAAL52AAFAAAABSABD
36 AAAL52AAFAAAABSABV
. . .