Introduction

The Oracle multitenant environment is a new architecture of Oracle Database, introduced in version 12c (12.1.0.1). It brings major changes to the way Oracle Database administrators think about the concept of databases and how they work (in a multitenant environment). One of the most significant changes is that many databases (up to 252) can share one database instance.

This chapter is focused on some of the security considerations concerning common and local users, roles, and privileges. The prerequisite for understanding recipes in this chapter is to have at least basic knowledge of fundamental multitenant concepts, such as what is a container database (CDB), pluggable database (PDB), root container, and seed.

Figure 1 shows the traditional architecture of Oracle Database.

Figure 1 - A traditional architecture

Figure 2 shows the separation of the data dictionary in a multitenant architecture:

Figure 2 - Data Dictionary separation

Figure 3 shows a multitenant architecture. To learn more about it, see the Oracle official guide, Oracle Database Concepts, 12c Release 1 (12.1), Part VI Multitenant Architecture.

Figure 3 - A multitenant architecture