Looking for Undocumented cool stuff...like...

[KenEwald]

select USER from dual;

USER is not a column in the dual table, yet it returns the current user ... that's cool.

Is there a web site with undocumented features?

[jmodic]

SYSDATE is also not a column in DUAL table, yet you've probably often used "SELECT SYSDATE FROM DUAL;". The same goes for UID, for example.

It is nothing misterious about USER, SYSDATE etc. They are normal built-in functions. The only thing that differs them from other built-in functions is that they require no parameters.

And they are all documented in SQL manual, so there is no need to look for them among "undocumented features"...

[KenEwald]

Oops. I wrote before I read .. sorry folks.