Markus Schiltknecht wrote:
>
> I'm questioning if a replication system can be written by only using
> triggers as hooks. AFAIK Slony-I uses triggers, so you can probably
> better comment on problems or limitations using triggers. For me a
> shared library with some hooks as C function calls seems a more
> plausible approach.
Of course not...
It is impossible to build a replication system entirely by only using
triggers...
But definitely, there is a set of common requirements among a variety of
replication systems. Moreover, such requirements are also useful to
other systems as well.
Roughly, the GAPI reflects any event inside a database system and allows
any application to intercept and modify them.
For instance, an event might be: 1 - database shutdown, startup 2 - connection shutdown, startup 3 - statement
reception 4 - parsing 5 - execution plan generation 6 - tuples written
Our current prototype covers some of them and some of them partially (2,6).
Besides, we also need the priority mechanism.
Best regards,
Alfranio Junior.