Upgrading Oracle

Oracle 10i is just around the corner, but recent surveys show that most of you are still using versions 8 or 8i. If you are considering upgrading from your current version, whatever it is, this Ask the Experts compilation can help. In it, Oracle gurus Brian Peasland, Karen Morton and Eli Leiba point out advantages of updating your software, how it will affect applications, hardware requirements and other issues to be aware of during the move.

Can you enumerate the differences between the different versions of Oracle (i.e. disadvantages and advantages)?
Brian Peasland: Oracle databases have been around for quite a while now. Oracle released their 9i (9.0.1) version about a year ago. Many companies are still using the 8i (8.1.x), 8 (8.0.x) and 7.x database versions. For the most part, everything that is available in a lower version will be available in a higher version as well. There are a few minor exceptions, but the Oracle databases tend to be backwards compatible. When Oracle releases a new version, their documentation contains a list of all the features new to that version. So it is worthwhile for the DBA to read this documentation to discover what is new in the database. To give you an idea of what is "new" consider this...Oracle 8i introduced many new features for the developer. With 8i, you could run Java in the database, you had expanded tools to help with object-oriented development and 8i introduced some enhancements to support larger databases (Materialized Views, additions to partitioning). Oracle 9i introduced many new features to help the DBA such as the ability to change database configuration "on the fly", enhanced availability and enhanced managability. The advantage of a higher version is that you have more features and better capabilities. You also stay current with the latest "supported" versions. The disadvantage of these new systems is that you have to convert your older databases to the newer versions. This can sometimes cause application changes as well. The advantage of staying at a lower version is that you know it works and you don't have to change a thing. The disadvantage is that you can't use any of the latest and greatest features and that you may lose support.

What are the main advantages of upgrading from Oracle 7 to Oracle 8i/9i?

1. adding objects to the database
2. adding new data type such as BLOB/CLOB
3. new administrative options like moving tables between tablespaces
4. many NEW dbms packages
5. writing JAVA code inside Oracle
6. passing parameters to sp with the NOCOPY Option
7. smart sqlloader options
8. can work with array types
9. the new log miner.