Suggestion on Reading a Oracle Data Model

Question

Background:

I am doing a self study on an Oracle Product (Argus Safety Insight), and I need to understand the database schema of this product. I have installed the database and loaded the schema successfully. I have also generated data model using "SQL DEVELOPER DATA MODELER".

Issue:

This schema has 500 tables and 700 views which together gives around 20K columns, I couldn't navigate through the data model due its huge size; SQL developer hangs.

Question:

Will you please help me with a tool or technique on how to read and understand the logical relationships between tables in such huge databases.

Answer 1

You have two issues.

1: Technical - 'sql dev hangs' - you're asking it to open something so big, it overwhelms the Java Virtual Machine (JVM). For really LARGE models, we recommend you bump this to 2 or even 3 GB.

To increase the memory for the JVM, you need to find the product.conf file for SQL Developer. On Windows, it's under AppData for your user, and roaming profiles. On a Mac/NIX, it's in your $HOME directory, and then in a .SQLDev 'hidden' sub directory.

The file is documented quite well, but you need to do something like -

AddVMOption -Xmx2048m

Save, then re-open SQLDev and your design.

2: Human - how do you make sense of hundreds or thousands of objects in a diagram? You just can't. So you need to find application-driving MAIN tables, and generate SubViews (a subset of the diagram) for easier digestion.

I talk about how to do this here.

Now that your objects are grouped by SubViews, you can now view, print, report, and search them by SubView as well.