Oracle Data Modeler - Diagram notation

Question

Is there a detailed notational guide for the Relational model diagrams generated by the Oracle Data Modeler?

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I'm using Oracle Data Modeler to generate Relational Models for an existing database. It generated a diagram, but I'm not able to decode all the notations in the diagram.

Some of the notations are:

1. arrows
2. asterisks (red)
3. Aphabetical notations (like P, F)
4. Symbols (like diamond, key)
5. Abbreviations (like IX)

By mere inference, the above correspond to:

1. foreign key references
2. ??
3. P - Private key; F - Foreign key
4. key - Private key
5. ??

However, I'm wondering if there is a detailed notational guide for the Oracle Data Modeler?

I searched for it online, but could find none.

Plagioclase

Also letter U exists there, it means Unique. – Sewellel

Answer 1

• P symbol before a Column name: the column is the "Primary key" ("P" for Primary) of the EntityType; Note that you can have two or more columns with a P symbol as a Primary key can be made of several columns

• F symbol before a Column name: the column is a "Foreign key" ("F" for Foreign) which mean this column is referencing the Primary Key of another entity; Not that you can have several Foreign keys

• PF symbol together: the column is both a Primary key and a Foreign key

• "*" symbol (red asterisk): the column has a NOT NULL constraint; in other words, you can't insert a row (also called an "instance" of the Entity Type) in this table without a value for this column)

• Diamond shape symbol (at the bottom of a Table): show the INDEXES on that table (in general the Primary Key is automatically an Index

Mousterian

the * we saw it on day to day basis when filling forms on the web. Funny enough, I just wonder if this is where the actual source of it. – Solitary

Answer 2

Red asterisks usually are mandatory, Diamonds in most ERDs indicate a relation to. pk and fk are private and foreign keys if I recall correctly. I'm not sure what you mean by arrows, do you mean crows feet notation?

Grow

Answer 3

I think data modeler has a section in the settings to show which ER notation it is using. One can change or see the notation there. for my mac;

Preferences -> Data Modeler -> Diagram -> Logical Model 

there you can see the used notation. And so that you can check online for more information of the arrows etc..

Colloquium