[GENERAL] maximum number of databases and / or schemas in a single database instance

The following page: http://www.postgresql.org/about/ mentions some limits but not the following: [1] maximum number of databases per database server instance [2] maximum number of schemas per database Is there empirical information on whether both these values can be as high as a few hundreds?

[GENERAL] strategies for segregating client data when using PostgreSQL in a web app

I would like to know what are the best practices / common patterns (or pointers to such) for using PostgreSQL in the context of a "big" web application with substantial data per user. Namely, we are designing an ERP / accounting / business intelligence Web Application where each client company wil