SQL: Structured Query Language - Oracle 10g Database Administration Concepts and Implementation Made Simple - page 27

Output:

Result
--------
DE

Example:

SELECT INSTR('CORPORATE FLOOR','OR', 3, 2)
"Instring"
FROM DUAL;

Output:

Result
----------
14

Similarly we can use INSTRB; for a single-byte database
character set, INSTRB is equivalent to INSTR. Lets suppose a
double-byte database character set.

SELECT INSTRB('CORPORATE FLOOR','OR',5,2)
"Result"
FROM DUAL;

Output:

Result
--------
27

Example:

SELECT LENGTH('SPIDERMAN') "Result"
FROM DUAL;