Understanding a database schema

Question

This should be a really simple question for any Oracle DBAs out there.

I just started on a new application and I asked to see the schema. I am not familiar with Oracle or its naming conventions at all. So I submit to you the following:

enter image description here

I'd like to know:

Why the separation from the top 2 fields and the rest? (I assume those are PK but it doesnt explicitly state as much)
What's the difference from the bolded fields and non-bolded?
What does 'l3', 'l5', etc indicate?
A couple other tables (not pictured) have 'U1' indicators where this pic has 'l3', what does that mean?

The questions have nothing to do with Oracle - only with whatever application you use to display the ER model. — user330315
– user330315, Commented Jul 17, 2013 at 17:27
Sorry, I have seen many db schemas and none have looked like this document, I assumed it was an oracle specific thing. You could have just removed the tag and updated the title, rather than posting a comment... — Mike Fielden
– Mike Fielden, Commented Jul 17, 2013 at 17:41

Thomas Erdman · Accepted Answer · 2013-07-17 16:21:07Z

5

To answer you questions:

The top two fields indicate the primary keys for the table
Bolded fields are required ( NON-NULL ) fields
"I" indicates that the columns are indexed
"U" indicates that the columns have a unique key associated with them

Hope this helps.

answered Jul 17, 2013 at 16:21

Thomas Erdman

1717 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Understanding a database schema

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related