Analysis of Dynamic Management Views for Monitoring Rolled Back Transactions

Correct Answer: B (sys.dm_pdw_nodes_tran_database_transactions)

Why this is the optimal choice:

• sys.dm_pdw_nodes_tran_database_transactions specifically tracks database-level transaction information across all nodes in the distributed SQL pool
• This DMV provides detailed transaction state information, including when transactions are in a rolled back state
• It shows transaction status codes that indicate rollback operations (transaction_state = 3 indicates rollback in progress)
• Since Azure Synapse Analytics uses a distributed architecture, this view aggregates transaction information from all compute nodes
• You can filter by transaction_state column to identify transactions that are actively rolling back or have been rolled back

Analysis of Other Options:

A. sys.dm_pdw_request_steps

• Not suitable: This view provides execution step details for queries but does not track transaction rollback status
• Useful for understanding query execution plans and performance bottlenecks, but not for monitoring transaction rollbacks

C. sys.dm_pdw_waits

• Not suitable: This view shows wait statistics for resource contention but doesn't provide transaction rollback information
• Helpful for diagnosing performance issues due to resource waits, but unrelated to transaction state monitoring

D. sys.dm_pdw_exec_sessions

• Not suitable: This view tracks session-level information but doesn't provide granular transaction rollback details
• Useful for monitoring active sessions and their general status, but lacks specific transaction state tracking

Implementation Approach:

To effectively monitor for rolled back transactions, query the sys.dm_pdw_nodes_tran_database_transactions view and filter for transactions where the transaction_state indicates rollback activity. This provides the most direct visibility into transaction failures that could be causing query performance issues or failures in your SQL pool.