Relationship Among Database Incarnations

Database incarnations can stand in the following relationships to each other:

■The current incarnation is the one in which the database is currently operating.

■The incarnation from which the current incarnation branched following an OPEN RESETLOGS operation is the parent incarnation of the current incarnation.

■The parent of the parent incarnation is an ancestor incarnation. Any parent of an ancestor incarnation is also an ancestor of the current incarnation.

■The direct ancestral path of the current incarnation begins with the earliest incarnation and includes only the branches to an ancestor of the current incarnation, the parent incarnation, or the current incarnation.
An incarnation number is used to uniquely tag and identify a stream of redo.

Incarnations of PDBs

A pluggable database (PDB) incarnation is a subincarnation of the multitenant container database (CDB) and is expressed as (database_incarnation, pdb_incarnation). For example, if the CDB is incarnation 5, and a PDB is incarnation 3, then the fully specified incarnation number of the PDB is (5, 3). The initial incarnation of a PDB is 0. Subsequent incarnations are unique but not always sequential numbers.

The V$PDB_INCARNATION view contains information about all PDB incarnations.

Use the following query to display the current incarnation of a PDB:
select PDB_INCARNATION# from v$pdb_incarnation where STATUS = ‘CURRENT’ and CON_ID = PDB_container_id;