Question

Caveats:

Let me first clarify that this is not a question about whether to use surrogates primary keys or not.

Also, this is NOT a related to identities (SQL Server) / Sequences (Oracle) and their pros / cons. I did get a fair bit of idea about that thanks to this, this and this

Question:

I come from a SQL Server background and have always used identity columns as surrogate primary keys for most tables.

Based on my knowledge of Oracle, I find that the nearest equivalent in Oracle are SEQUENCES which can be used to simulate something similar to Identity in SQL server.

As I am new to Oracle and my database has 100+ tables, the main thing that i am concerned about :-

Considering i have to create a sequence for each table in Oracle (almost), would this be the standard accepted implementation for simulating Identity or is there a better / easier way to achieve this kind of implementation in Oracle?

Are there any specific GOTCHA’s related to having so many sequences in Oracle?

The system supports both Oracle 10G and 11G

Answer 1

Considering i have to create a
sequence for each table in Oracle
(almost), would this be the standard
accepted implementation for simulating
Identity or is there a better / easier
way to achieve this kind of
implementation in Oracle?

Yes, it is very typical in Oracle to create a sequence for each table. It is possible to use the same sequence for several tables, but you run the risk of making it a bottleneck by using a single sequence for many/all tables: see this AskTom q/a

Are there any specific GOTCHA’s
related to having so many sequences in
Oracle?

None that I can think of.