Find a TABLE size in Oracle.

I've heard this question so many times so decided to answer on it one time and forever :).

You don't need any DBA permissions for this since this view is available for all users!

View: USER_EXTENTS

so to check a table size just select from it:

select sum(de.bytes)/1024/1024 MB_size from user_extents ue
where ue.segment_name='YOUR_TABLE';

That is all!