Explore the Oracle data dictionary

I have published a free web-based utility.

https://www.viskey4you.com

It allows to explore the Oracle data dictionary.
You will see: DBA_TABLES, DBA_TAB_COLUMNS, .... and their relations in a kind of ERD diagram.
It is also possible to create the select statements and joins against the dictionary views on the fly.

In addition there is a collection of sample DDL commands for the most popular object types.
So you will see the correct sample DDL for the creation of tables, views, mviews, partitions,...