The point with the trigger is that the trigger isn't a behavior of the table itself. You cannot ask the table to do something, simply because it has a trigger on it. To have the trigger code execute, you must perform an action upon the table. The database engine, upon seeing that action performed upon the table, executes the code in the trigger. It's not a behavior of the table, but a behavior of the engine.

Another way to put it would be this - if it was a behavior of the table, you would be able to move the table from one schema to another and the behavior would move with it. But, you can't do that in any RDBMS I've ever worked with.

Another way to think about it would be this - if it was an behavior analogous to the OO sense of the word, it would only be allowed to affect its state and request that the objects it contained affect their state. But, most non-trivial triggers I've seen are meant to affect the state of other tables, given the new values in this table.

As for stored procedures ... I can see advantages to putting code in stored procedures ...... if you're remediating an existing application and the current developers are dunces. Otherwise, why would you put the code in the database as opposed to putting in a middle-tier? You could even restrict access to the database to that middle-tier, forcing all access to be moderated the same way it would be moderated through the stored procedures. But, instead of having to program in two languages (one of which is going to be substandard), you would be able to keep all your code in one language (Perl, for example) and would not be tied to one datastore vendor.

------
We are the carpenters and bricklayers of the Information Age.

Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose

I shouldn't have to say this, but any code, unless otherwise stated, is untested

In reply to Re^6: OO concepts and relational databases by dragonchild
in thread OO concepts and relational databases by dragonchild

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