When should you use java stored procedures with an Oracle database … what are the drawbacks? [closed]

Answer 1

Only when you can't do it in PL/SQL ( or PL/SQL proves to be too slow, which would be pretty rare I believe ).

As a case study... We had a single java stored procedure running in production ( Oracle 9i ), it was originally written in java because at the time we thought java was cool, Something I've long since changed my mind about. Anyway. One day, the DB crashes, after it reboots the java SP doesn't work. After much back and forth with oracle support, they don't really know what the problem is and the only suggestions they have involve much downtime. Something which wasn't an option. 30 minutes later I had rewritten the java SP in PL/SQL.

It now, runs faster, is oracle "native" , shares the same deployment process as other objects and is easier to debug.

PL/SQL is a very capable language. If you are writing Stored Procedures, please take the time to learn it rather than just doing things in java because thats what you know.

Answer 2

The main advantage is access to the API's and language features not found in PL/SQL. For example, I have used them for regular expression processing, file/directory manipulation and XML parsing.

There are a number of disadvantages:

• Poor tool support
• Lack of control over the JVM
• DBA's often aren't trained in Java. In order to support your production code you'll either either need to give your DBA's more training or hire Java-trained support staff

Moving the Java to an application server is often a better approach as this counteracts the disadvantages. There is excellent tool support, great control over the JVM and there are heaps of people trained up in the popular application servers so finding support staff is easy. There is the opportunity cost of the performance hit moving away from the database but keeping Java close to the database doesn't give you great performance gains anyway.

You definitely need a reason to use Java in the database over a) PL/SQL stored procedures or b) Java outside the database.