Oracle Database 19c: Performance Management and Tuning Intermediate Practice Exam: Medium Difficulty 2025

A DBA notices that several sessions are waiting on 'cursor: pin S wait on X' events during peak hours. The application uses a shared pool of 2GB, and AWR reports show high version counts for several SQL statements. What is the most likely cause and appropriate solution?

An OLTP database experiences performance degradation during month-end processing. The AWR report shows a high 'DB file sequential read' wait time and the Top SQL section reveals multiple queries performing index range scans on a heavily fragmented index. What combination of actions would most effectively address this issue?

A database administrator is analyzing memory allocation after observing ORA-04031 errors. The Automatic Shared Memory Management (ASMM) is enabled with SGA_TARGET set to 8GB. V$SGASTAT shows the shared pool at 1.5GB with 85% utilized, but V$SHARED_POOL_ADVICE suggests optimal size should be 2.5GB. What is the most appropriate action?

During SQL tuning, you execute EXPLAIN PLAN for a query that joins four tables. The execution plan shows a HASH JOIN operation with a cost of 1500, but the actual execution takes significantly longer than expected. What is the most likely reason and how should you investigate further?

An application experiences intermittent slowdowns. AWR reports show that during these periods, the 'log file sync' wait event spikes significantly while 'log file parallel write' remains stable at low values. What does this pattern indicate and what should be investigated?

A performance engineer needs to tune a query that performs poorly despite having appropriate indexes. The SQL has bind variables and the execution plan varies significantly between executions with different bind values. Which Oracle feature should be used to address this issue?

A database is configured with Automatic Memory Management (AMM) with MEMORY_TARGET set to 16GB. After a system reboot, the database fails to start with an ORA-00845 error indicating insufficient /dev/shm size. The Linux server has 32GB of physical RAM. What is the correct resolution?

While reviewing an AWR report, you notice that the Buffer Cache Hit Ratio is 98%, but the 'db file scattered read' wait event is in the top 5 wait events with significant time. What does this indicate about database performance?

A DBA uses SQL Tuning Advisor to analyze a poorly performing query. The advisor recommends creating a SQL Profile with an estimated improvement of 85%. Before implementing the profile in production, what is the best approach to validate this recommendation?

A data warehouse query uses a large hash join between two tables. The execution plan shows 'HASH JOIN' but V$SQL_WORKAREA shows the operation spilled to disk with TEMPSEG_SIZE indicating significant temporary tablespace usage. What is the most effective solution to improve this specific query's performance?