[miahi]

Actually, the whole "create database" is misleading when comparing the two.

For Oracle, a "database" is the a server instance; you create the database when you install the software (without creating a "database" you don't actually have anything running). For postgres, a database is just a level of data organization/segregation.

In an oracle instance you only have a single database. The equivalent of the postgres "database" would be "user/schema" in Oracle.

[leandrod]

Not at all. Because Oracle does not have multiple databases per instance does not equal a PostgreSQL database to an user in Oracle. On the contrary, it means PostgreSQL is way more flexible, because there we have and databases, and users and schemas as ISO meant it.