Re: Access to Oracle

There's only one piece of advice you need today -

Don't commit to any deadlines until you've tried a test porting of an application from Access to Oracle.

For tomorrow, here are a number of areas of technical risk;

Namespace Issues.

1. table name length limits (30 in Oracle, first character is a letter, no spaces etc. etc.) - in Access you can innocently use more than 30 and cause infinite pain when you try to move your objects over (because many parts of an application may have already been written to use the longer table names).
2. Middleware issues.

How are you going to connect your application / front-end etc. to Oracle?

OCI (C)?, ODBC ?, OLE-DB?, OO4O (OLE)?, JDBC?, IIOP ?, Corba and Java Beans?, Java Servlets?

You need to choose the best method. Then you need to test some of the most recent drivers (whether from MS, Oracle or 3rd party). Some middleware drivers have got memory leaks which will ruin your entire day. (I'm not mentioning any names but don't assume big=best).

3) Application design.

Many apps that work well with Access (with lots of local RAM acting as a cache) can crawl when they need to talk to Oracle. This of course is a scalability problem caused by Access, not by Oracle. (i.e. Access's over-reliance on being able to cache most of the data it needs locally in RAM).

4) Performance Tuning of the server.

This can be complicated, but there are some simple things you can do in the first place. Don't blindly accept default initialisation parameters for instance.

5) Familiarity with the OS hosting the database.

How familiar are you with the OS on which you are going to run Oracle?

More importantly - do you trust the OS to be reliable. Oracle is often more reliable than the OSes it can be run on. Buying Oracle does not insulated you from OS-induced problems.

6) Vendor interoperabiliy risk.

If your OS vendor doesn't like your database vendor, do you think you'll have an easy time of it?

Do you trust your OS vendor not to place artificial barriers or hurdles in your way. I've seen this happen once and it was simply not funny.

7) The desire to make money.

Sure you may like to start using Oracle for all the right reasons, but if you rush it you'll make a hash of it and you won't be very popular.

So this issue boils down to - how much time and resources are you willing to commit to learning Oracle (before you see any payoff)?

David P.

Oracle Certified DBA.

matt wrote:
>
> Hi there,
>
> We normally develop our websites using an Access or MSQL backend
> database. For our next project we've decided to use Oracle 8i instead.
>
> We're expecting the software to arrive next week, but in the meantime I
> need to start work on developing the structure.
>
> Are there any issues involved if I develop the database in Access and
> then migrate to Oracle at a later date?
>
> Thanks for any advice,
>
> Matt Pryor
Received on Wed May 03 2000 - 00:00:00 CDT