Geoff Worboys wrote:

>
> Side Note: The above examples (logmanager, IBO DML stuff
> and some of my own work) make me wonder whether it would be
> possible to have "generic" table triggers. That is; define a
> single before or after trigger than fires against all DML
> (insert/update/delete on all user tables). To be useful such
> triggers would need ways to interrogate what table is currently
> being processed and what fields it has... so I expect this
> would be non-trivial. However it would mean that instead of
> needing some 200 functionally identical triggers for 200 tables
> you could have just one. (Just a thought.)
>

I did that in Netfrastructure -- and it's a huge win. Netfrastructure,
however, uses embedded Java as the trigger environment, giving it a
little more computational umph. Firebird, I'm afraid, uses the BLR
engine as the trigger environment, so there is absolutely no way to make
table references soft. There was quite some chitchat a year ago about
pluggable engines, but design was specific to Firebird 2, so that's not
going to help much going forward.

If I were to make a recommendation going forward, I would suggest find a
tame JVM, embedding it in Vulcan, and support Java based triggers. Yes,
it's a big piece of work, but work well worth doing. The down side,
unfortunately, will be a large chorus "but I don't know Java and I want
my xxx".

But a single replication trigger handling insert, update, and delete for
all tables is really sublime.


--

Jim Starkey, Senior Software Architect
MySQL AB, www.mysql.com
978 526-1376