To determine if a recently executed query on Pool1 utilized the result set cache, two effective methods are available:

B. Review the sys.dm_pdw_exec_requests dynamic management view in Pool1

• This dynamic management view (DMV) provides comprehensive information about query execution in Azure Synapse Analytics dedicated SQL pools. It includes the result_cache_hit column, which explicitly indicates whether the query result was served from the cache (value = 1) or required computation (value = 0). Querying this DMV directly on Pool1 allows real-time verification of cache usage for specific query executions.

C. Use the Monitor hub in Synapse Studio

• The Monitor hub in Azure Synapse Studio offers a graphical interface to analyze query performance and resource utilization. It provides detailed metrics and logs for executed queries, including cache hit/miss information. This method is particularly useful for users who prefer a visual approach without writing T-SQL queries, and it integrates seamlessly with the Synapse Analytics environment.

Why other options are less suitable:

• A (sys.dm_pdw_sql_requests): While this DMV contains query execution details, it focuses on SQL request steps rather than comprehensive cache utilization metrics. The result_cache_hit column is more reliably found in sys.dm_pdw_exec_requests.
• D (AzureDiagnostics table in la1): Although diagnostic logs in Log Analytics workspace la1 contain query execution data, they may not consistently include specific result set cache hit indicators. The logging configuration and schema might not capture this granular cache information reliably.
• E (sys.dm_pdw_request_steps): This DMV breaks down query execution into individual steps but doesn't provide direct cache hit information at the overall query level. It's more useful for analyzing query execution plans rather than cache utilization.

The combination of B and C provides both programmatic (DMV) and administrative (Monitor hub) approaches, covering different user preferences and scenarios for verifying result set cache usage.