I want to create a data dictionary document from an existing Oracle database. Can anyone please tell me how I can do that? Is there any SQL command available to create data dictionary?
The CREATE DATABASE command creates the Data Dictionary. But this is a one-time operation. If you have your database created, you do not create a data dictionary again. However, you may be talking about reverse-engineering the schema design. There are tools which can do this for you. Oracle Designer and Microsoft Visio have the ability to connect to the database and reverse-engineer the ERD. Those products work great but can be pricey. I prefer to use
which is much cheaper. If you want to reverse-engineer the DDL statements to create an object, you can do something similar to the following: