Free Practice Questions for Oracle 1z0-076 Exam

The process of performing a rolling release upgrade in a Data Guard environment using a logical standby database generally involves these steps:

Raise the compatibility level on both databases (1):Ensuring both the primary and logical standby databases are operating with the same and correct compatibility level is essential before starting the upgrade process.

Upgrade the logical standby database (5):Apply the database upgrade to the logical standby first, which allows the primary database to continue serving the workload without interruption.

Restart SQL Apply on the upgraded logical standby database (2):Once the logical standby has been upgraded, SQL Apply must be restarted to apply the redo data from the primary database, which is still running the earlier version.

Perform a switchover to the logical standby database (4):After confirming that the logical standby database is successfully applying redo data, perform a switchover to make it the new primary database.

Upgrade the old primary database (6):With the new primary database now in place, upgrade the old primary database (which is now the new standby) to the new Oracle Database release.

DB_NAME (A):The name of the database, which should remain consistent across the primary and standby databases.

db_file_name_convert (C):This parameter helps define the mapping of data file names from the primary to the standby database, which is crucial during the creation and operation of a standby database.

COMPATIBLE (D):The compatibility level can influence the features that can be used on the standby database and must be consistent with or higher than that of the primary database, especially after upgrades.

STANDBY_ARCHIVE_DEST (F):This parameter specifies the destination of archived redo log files on the standby database, which is important for log transport and apply services.

Block change tracking is a feature that enhances the efficiency of incremental backups by recording changed blocks in a tracking file. When used with Oracle Active Data Guard:

It starts the RVWR process on the physical standby database instance (A):When block change tracking is enabled on a physical standby database, the Recovery Writer (RVWR) process is initiated. This process is responsible for recording the changes to blocks in the block change tracking file, which is then used to optimize incremental backups.

Stop the Observer on host1 to ensure that there are no conflicts between the instances of the Observer running on different hosts.

Update the Data Guard Broker configuration with the new hostname for the Observer. This step is crucial to redirect the Data Guard Broker to communicate with the Observer on the new host.

Start the Observer on host2 to resume its operations in the new environment.

Disabling and re-enabling Fast-Start Failover (steps 2 and 4) are not strictly necessary for moving the Observer to a new host. These steps would be more relevant if changes to the configuration of Fast-Start Failover itself were required, which is not the case when simply relocating the Observer.

The compatible parameter on a standby database that is applying redo, must be equal to or greater than the compatible parameter on the primary that is shipping redo to that standby (A):This ensures that the standby database can apply redo from the primary, even after the primary has been upgraded. TheCOMPATIBLEparameter setting on the standby database should not preclude it from understanding the redo it receives.

Modifications to the data dictionary on the primary database caused by the upgrade, are applied on a physical standby database (C):When the primary database undergoes a non-rolling upgrade, any resulting data dictionary changes are transmitted through redo data and applied to the physical standby database.

Based on Oracle Database 19c: Data Guard Administration documents, the three measures that can prevent clients from connecting to the wrong database instances during switchovers, failovers, or regular operations in a Data Guard environment are:

B. The standby database services must be defined statically with the Listeners running on the standby database hosts.

D. The client applications must use the correct TNS entries when requesting connections to the database instances.

E. Client TNS entries for the databases use the correct service names for the intended service.

In an Oracle Data Guard configuration, correctly configuring Oracle Net Services (including TNS entries and listeners) is crucial for ensuring that clients connect to the appropriate database instance, whether it's the primary or standby. Defining services on the standby database and associating them with listeners ensures that client applications can connect to the standby when needed, especially useful in a role transition or when the standby is open for read-only access or real-time query. It's essential that TNS entries used by client applications specify the correct service names that correspond to the intended database roles, such as primary or standby. This setup facilitates seamless connectivity to the appropriate instance based on the role, especially critical during switchovers and failovers when the roles of the databases change.