I’ve seen address tables locked down because a bad schema design required a relationship to an account table. A duplicate table had to be created for non-account addresses.

I watched a 5 minute “I’ll just change that in the DB” turn into a 2 hour frustration session by the DB due to the mountain of RI constraints.

I’ve spent hours trying to track down unclear error messages when I tried to delete a record from a table that had a RI because the DB abstraction layer I was using didn’t understand a new error code.

I’ve been stuck twiddling my thumbs because the DBA was on vacation or was out sick that week and I needed a change made.

I’ve gone drinking because I found out that there was no source control on a database’s stored procs and it was either drink or stab someone.

I’ve watched programs do no validation in their apps or pages because they assumed the database was going to catch any errors. You know, because the DBA said so.

In many years and many companies of many sizes I’ve rarely if ever seen apps that were less stable when backed into databases that lacked RI. I can’t ever remember a time I spent hours tracking down a bug due to invalid data in the database but I’ve wasted days and weeks trying to work around constraints.

Milage varies but that’s what I’ve seen.

Now, what if you do load-balancing, and have several apps of the same kind hitting your database at the same time?

you’ll need some central integrity checking in your database then.

regards,

Martin

I establish the rules of my data formatting and the database or word processor ensures that all data conforms to those rules. The database is just an application at heart, one which is built to store, retrieve, recover, constrain, and manage gobs of data.

On a side note, there is one huge advantage to a well-designed database. It can change its access path based on the amount and type of data put into it. It can switch between brute force (full table scan), indexed access (unique location and index scanning), and hashing. Furthermore, the databases are created by tons of talented developers with a huge base of users testing. Not only are the database owners testing it, but so are the database users. There are few applications that can say they have had that many users test their system - EVER.

Databases are not bit boxes. While they do seem to serve that purpose, they are much more complex on the inside than is outwardly noticeable. If developers do not understand what it is doing, why it is doing it, and how to take advantage of it, I would not want them to implement data management in my applications.

Frankly, I’ve settled for laughing.