Geting value count from an Oracle Table

Question

I have a table, that contains employees. Since the company I\'m working for is quite big (>3k employees) It is only natural, that some of them have the same names. Now they

Answer 1

This can be easily done with a count over partition:

SELECT NAME, SURNAME, USERNAME, COUNT(*) OVER (PARTITION BY NAME, SURNAME)
FROM
YOUR_TABLE;

Answer 2

Adding the flag to Daniel's answer...

SELECT NAME, SURNAME, USERNAME, DECODE(COUNT(*) OVER (PARTITION BY NAME, SURNAME), 1, 'N', 'Y')
FROM
YOUR_TABLE;

Please note that Oracle SQL has no support for booleans (sigh...)