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. ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq