> Hi all,
>
>   I think the subject of this mail tel everything.  I search several
> list and haven't found an answer to my question.  If Slony-I cannot do
> the job is Mammoth can do it?  Or any other solution to replicate data
> on a slave server!

You mean that you have a PostgreSQL postmaster that has 250 databases
(e.g. - you ran createdb 250 times) and each of those has ~150 tables?

That seems like a case that will not likely turn out well with Slony-I.

The trouble is that Slony-I replicates from *a database* at a time.

If you have 250 databases on that PG cluster, then you need to have 250
slon processes, and, more than likely, 250 Slony-I clusters to manage.

Further, supposing you want to have two backup servers, that'll mean...

- 750 slon processes
- For each one, probably 4 connections, hence 3000 database connections,
1000 per postmaster

You'll find memory consumption to be hurtful, and this represents a pretty
big "thundering herd" of replication apparatus.

I'm not sure if Mammoth would provide you a better or worse experience, in
this scenario.  I think you'll need to contact the vendor about that.

The other possibility that I'd point to for situations like this is the
new-in-version 8 Point In Time Recovery system for PostgreSQL.  It will
NOT allow you to use the standby server(s) to respond to queries, alas. 
But it would inexpensively address your "explosion" of schemas.