Retrieving Username Using Oracle Triggers

Question

I am new to using triggers. What function can I use to determine who disabled my trigger?

For instance:
Someone is updating the row, and I want to know who updated the row.

I am using Oracle 10g.

Answer 1

SELECT sys_context('USERENV', 'SESSION_USER') FROM dual; 

or

 SELECT sys_context('USERENV', 'SESSION_USERID') FROM dual;