What's the difference between betwwen 2 DB and 2 Schema My question is : what is the difference between the two next mode in PostgreSQL, for an production application.


using two DB in the same SGBD (the same table-space and HDD)
Or using two schema in the same DB


What about response time &amp; performance ?
By default, PostgreSQL's databases cannot see each other and you cannot query between them. 

You can query between, or have foreign keys between PostgreSQL schemas.

If you want strong multi-tenant client segregation, use distinct databases.