1z0-076 Exam Dumps - Oracle Database 19c: Data Guard Administration

In an Oracle Active Data Guard environment:

• B: Read-mostly reporting applications that utilize global temporary tables to store session-specific data can be effectively offloaded to an Active Data Guard standby database, reducing the load on the primary database.
• C: Sequences can be used with global temporary tables on an Active Data Guard standby database to support certain types of read-mostly applications, though some restrictions on sequence use may apply.
• E: In Oracle Database 19c and later, DML redirection allows DML operations performed on an Active Data Guard standby database to be transparently redirected to the primary database. This is part of the DML Redirection feature.

Option A is incorrect because not all PL/SQL blocks run on an Active Data Guard standby database can be redirected to the primary database. Some PL/SQL executions, specifically those that would attempt to make changes to the database, are not supported on the standby.

Option D is incorrect because DDL operations on private temporary tables are not redirected; instead, private temporary tables are session-specific and are not persisted on disk, so they do not generate redo and are not applicable to an Active Data Guard standby.

References: The behavior and capabilities of Active Data Guard standby databases are documented in the Oracle Data Guard Concepts and Administration guide and the Active Data Guard documentation.

To reduce the redo apply lag on standby databases, one could increase the size of the standby redo log files. Larger redo log files can accommodate more redo data, which may reduce the frequency of log switches and allow for more continuous application of redo data. Additionally, lowering the DB_BLOCK_CHECKING parameter to MEDIUM or LOW on the standby databases can help improve redo apply performance. High block checking can impose additional CPU overhead during the application of redo data, potentially increasing apply lag times. By reducing the level of block checking, you can lessen this overhead and help reduce the apply lag ​​.

• The command performs a comprehensive set of database checks prior to a role change (A): The VALIDATE DATABASE command in Data Guard Manager (DGMGRL) is designed to perform an exhaustive check of a specified database's readiness for a role change, such as a switchover or failover.
• The command performs network connectivity checks between members of a broker configuration (C): One of the checks includes verifying that the necessary network connectivity exists between the databases in a Data Guard Broker configuration.
• The command can be used for a logical standby database (D): The VALIDATE DATABASE command is versatile and can be used for both physical and logical standby databases to ensure their readiness for role changes.

References:

• Oracle Data Guard Broker documentation
• Oracle Data Guard Concepts and Administration Guide

The execution of the UNSKIP procedure is designed to remove SQL Apply filters that have been previously set up on a logical standby database. Based on the provided statements, the UNSKIP procedure is directed to delete any SQL Apply filters for DML statements associated with objects in the 'HR' schema that start with 'EMP'. Since both SKIP procedures had the same schema name ('HR') and statement type ('DML'), and the UNSKIP procedure uses a wildcard (%) for the object name, it will successfully remove both of the SQL Apply filters for 'EMP_NEW' and 'EMP_OLD', as both object names match the pattern provided in the UNSKIP procedure.

References:Oracle's Data Guard documentation and SQL Language Reference provide insights into managing SQL Apply filters on a logical standby database using the DBMS_LOGSTDBY package. This includes adding and removing filters through SKIP and UNSKIP procedures.

To automate the instantiation of a PDB in the standby database after creating a remote clone in the primary database, certain conditions must be met:

• Open PDBI (remote clone source) in Read Only (A): The source PDB from which the clone is created must be open in read-only mode to ensure a consistent state during cloning.
• Set STANDBY_PDB_SOURCE_FILE_DIRECTORY to in the london database (C): This parameter specifies the location on the standby database where the files from the source PDB should be placed.
• Set STANDBY_FILE_MANAGEMENT to auto in the london database (F): This parameter automates the management of file changes on the standby database when structural changes occur on the primary database, ensuring that the clone operation is reflected automatically on the standby.References:
• Oracle Multitenant Administrator's Guide
• Oracle Data Guard Broker documentation