Which dynamic management view should you query?

You have a SQL pool in Azure Synapse.

You discover that some queries fail or take a long time to complete.

You need to monitor for transactions that have rolled back.

Which dynamic management view should you query?
A . sys.dm_pdw_request_steps
B. sys.dm_pdw_nodes_tran_database_transactions
C. sys.dm_pdw_waits
D. sys.dm_pdw_exec_sessions

View Answer

Answer: B

Explanation:

You can use Dynamic Management Views (DMVs) to monitor your workload including investigating query execution in SQL pool.

If your queries are failing or taking a long time to proceed, you can check and monitor if you have any transactions rolling back.

Example:

— Monitor rollback

SELECT

SUM(CASE WHEN t.database_transaction_next_undo_lsn IS NOT NULL THEN 1 ELSE 0 END),

t.pdw_node_id, nod.[type]

FROM sys.dm_pdw_nodes_tran_database_transactions t

JOIN sys.dm_pdw_nodes nod ON t.pdw_node_id = nod.pdw_node_id GROUP BY t.pdw_node_id, nod.[type]

Reference: https://docs.microsoft.com/en-us/azure/synapse-analytics/sql-data-warehouse/sql-data-warehouse-manage-monitor#monitor-transaction-log-rollback