Oracle Updated 1z0-076 Exam Questions and Answers by tymon

The SQL apply lag on a logical standby database can be caused by several factors:

A: An undersized undo tablespace can lead to delays in SQL apply operations as it may not be able to handle the volume of undo records generated by the SQL apply process.

B: SQL apply operations that do full table scans can consume significant system resources, potentially leading to higher apply lag.

C: An increased number of bulk updates on the primary database may generate a large volume of redo data, which can cause apply lag if the logical standby cannot apply the changes quickly enough.

F: An undersized shared pool may affect the parsing and execution of SQL statements by SQL apply, which can contribute to the apply lag.

Option D is less likely to be a direct cause of SQL apply lag compared to bulk updates, as inserts generate new data rather than modifying existing data, which SQL apply can typically handle more efficiently.

Option E is incorrect because the size of the standby redo log files on the primary database impacts redo transport lag, not SQL apply lag.

D. The database role indicated byFS_FAILOVER_STATUSas BYSTANDER implies that the database is a standby database in the Data Guard configuration. This means the database is neither a primary database nor an active failover target.

E. Since theFS_FAILOVER_OBSERVER_HOSTcolumn showscats, it suggests that this is the host on which the observer would run. However, because theFS_FAILOVER_OBSERVER_PRESENTcolumn is not shown, we cannot definitively state if the observer is currently connected or not. IfFS_FAILOVER_OBSERVER_PRESENTis 'YES', the observer is connected, if 'NO', then it's not. In the absence of this column's output, the best assumption based on the available data is that the observer is not connected.

The output shows that theFS_FAILOVER_STATUSisBYSTANDER, which indicates that the database in question is not actively involved in a fast-start failover configuration as a primary or standby. It is in a bystander role, meaning that while it is part of a Data Guard configuration, it is neither a target for failover nor actively participating in failover operations. Additionally,FS_FAILOVER_OBSERVER_HOSTshows 'cats', which indicates the host where the observer process is expected to run. However, since there is no information about the observer being present, we can infer that although 'cats' is designated for the observer to run, the observer is not currently connected to this database.

References

Oracle documentation on Data Guard configurations and theV$DATABASEview which provides information about the fast-start failover status and observer host.

Real-Time Query is a feature that allows queries to be run on a physical standby database while it is applying redo data. The relevant truths about it are:

Setting standby_max_data_delay=0 requires synchronous redo transport (A):For the real-time apply feature to function with no data delay (zero delay), synchronous redo transport must be used. This setting ensures that the data on the standby database is as current as possible before queries are executed against it.