Well there are 2 gud tools existing for this.
1. SQL Navigator
SQL Navigator® provides the tools you need to cut Oracle PL/SQL server-side development time in half.
PL/SQL development can be a tedious and time-consuming job – often monopolizing the valuable time and efforts of Oracle developers. SQL Navigator® is a PL/SQL development solution that streamlines workflow by adding a drag-and-drop, graphical user interface to the PL/SQL development environment.
SQL Navigator speeds the development of Oracle-based applications and combines coding, tuning, debugging, Web development and version control to deliver higher quality applications and save valuable time.
(This requires a license || a crack
)
Download Page Link : http://www.quest.com/sql-navigator/
2. Oracle Developer by Oracle it self
I recommend using this, since its free and has all the functions need.
Download Link : Click Me