5.1 Understanding the Installation Choices
Learn about the installation choices in Oracle APEX.
Oracle Database 12c Release 1 (12.1) introduces the multitenant architecture. This
database architecture has a multitenant container database (CDB) that includes a root
container, CDB$ROOT, a seed database, PDB$SEED, and
multiple pluggable databases (PDBs). Each pluggable database is equivalent to a separate
database instance in Oracle Database release 11g. The root container,
CDB$ROOT, holds common objects that are accessible to every PDB
utilizing metadata links or object links. The seed database, PDB$SEED,
is used when creating a new PDB to seed the new database. The key benefit of the Oracle
Database 12c or later multitenant architecture is that the database resources, such as
CPU and memory, can be shared across all of the PDBs. This architecture also enables
many databases to be treated as one for tasks such as upgrades or patches, and backups.
When configuring multitenant architecture, Oracle APEX is installed in the root container database by default in Oracle Database 12c Release
1 (12.1). In the default installation the root container, CDB$ROOT,
includes the APEX_040200 schema to store the common database objects
for the APEX engine such as packages, functions, procedures and views. The seed database,
PDB$SEED, also includes the APEX_040200 schema to
store the tables that are part of the APEX engine.
You can create a new PDB by copying PDB$SEED, which includes the
APEX_220100 schema if Oracle APEX release 22.1 is installed common in the CDB. As such there are multiple copies of the
Oracle APEX engine tables and only single copies of the Oracle APEX engine packages, functions, procedures and views. Each PDB will have the
APEX_220100 schema and have its own copy of the Oracle APEX engine's tables so that it can hold the metadata for the APEX applications defined within that PDB.
Tip:
Oracle recommends removing Oracle APEX from the root container database for the majority of use cases, except for hosting companies or installations where all pluggable databases (PDBs) utilize Oracle APEX and they all need to run the exact same release and patch set of Oracle APEX.