A financial services application is experiencing severe performance degradation during its nightly batch processing. An AWR report for the period shows the top wait event is 'latch: cache buffers chains', with a high number of consistent gets. The primary table involved in the batch job is frequently accessed via a non-selective index. Which action is the most direct and effective way to mitigate this specific latch contention?
A database is configured with Automatic Memory Management (AMM) by setting MEMORY_TARGET. After a system reboot, the database fails to start, and the alert log shows an ORA-00845 error. What is the most likely cause of this error?
You are tasked with analyzing the performance impact of a major application upgrade before deploying it to production. The goal is to test the exact production workload against the upgraded database environment to identify any SQL regressions. Which two Oracle features should be used in combination to achieve this? (Select TWO)
A query against a large, partitioned table is performing poorly. The execution plan reveals that the optimizer is performing a full scan on all partitions, even though the WHERE clause contains a filter on the partitioning key column. You have confirmed that optimizer statistics are up-to-date. What is the most probable reason for the lack of partition pruning?
True or False: When using the In-Memory Column Store, the `INMEMORY` clause can be applied at the tablespace level, causing all new tables and partitions created in that tablespace to be automatically enabled for In-Memory population.
You are managing a database for an e-commerce platform that experiences very high transaction rates. Users report intermittent slowdowns. Your analysis of ASH data reveals frequent waits for 'log file sync' and 'log file parallel write'. Which of the following is the most appropriate first step to diagnose the I/O subsystem's contribution to this problem?
A DBA is trying to improve the performance of a specific SQL statement. They run the SQL Tuning Advisor, which recommends creating a SQL Profile. What is the primary function of a SQL Profile?
An administrator is investigating high PGA usage. The `V$PGASTAT` view shows a large value for `total PGA allocated` and a significant number of `workarea executions - multipass`. What is the most direct way to get a recommendation for sizing the PGA to reduce multipass executions? ```sql -- Query executed by DBA: SELECT * FROM V$PGA_TARGET_ADVICE; ```
A system is experiencing high `buffer busy waits`. An analysis of `V$WAITSTAT` and segment statistics from an AWR report indicates the contention is on data blocks belonging to a single, heavily inserted table. The application uses a sequence to populate the primary key. Which two actions could help alleviate this specific type of contention? (Select TWO)
**Case Study**: A retail company runs its primary OLTP database on a 2-node Oracle RAC 19c environment. During peak holiday sales, the system experiences significant performance issues. The business requires that the database remains highly available and that the performance issues are resolved without application code changes. An AWR report from the peak period shows the top timed foreground events are 'gc cr block 2-way', 'gc current block 2-way', and 'DB CPU'. The 'Interconnect Ping Latency Stats' section of the report indicates low latency, suggesting the private network is healthy. Further analysis of the 'SQL ordered by Cluster Wait Time' section reveals that a small number of UPDATE statements against the `INVENTORY` table are responsible for the majority of the 'gc current block' waits. The `INVENTORY` table is frequently updated by transactions originating from both nodes as sales are processed. The application logic reads the current stock level, updates it, and commits. The table is not partitioned and has a standard B-tree index on the `PRODUCT_ID` primary key. Given this information, what is the most appropriate solution to mitigate the 'gc current block 2-way' contention and improve performance?