Oracle SQL Developer
Oracle SQL Developer is a free graphical tool for database development.
Using SQL Developer, you can browse database objects, run SQL statements and SQL scripts, and edit and debug PL/SQL statements.
You can also run any number of provided reports, as well as create and save your own.
SQL Developer can connect to any Oracle Database version 9.2.0.1 and later and runs on Windows, Linux, and Mac OSX.
Architecture
Oracle SQL Developer was developed in Java leveraging the Oracle JDeveloper IDE framework.
Default connectivity to the database is through the JDBC Thin driver (no Oracle Home required); the JDBC Type 2 driver (OCI client side driver) is also supported.
There is a separate release available bundled with JRE 1.5, with an additional tools.jar to support Windows clients.
Non-Windows clients only need JDK 1.5. or later.
Installation is performed simply by unzipping the downloaded file.