Trigger to capture the username

How can I capture the username that is updating a particular table ?
I can write a update trigger on the table but how to get the username that is updating that table ??

Is there any other way to capture this information ??

Any help will be appreciated.

Got the answer. Please close the thread.

Just use the USER pseudo-variable....

Code:

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SQL> select USER from dual;

USER
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SYSTEM

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