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title description author ms.author ms.reviewer ms.date ms.service ms.subservice ms.topic dev_langs monikerRange
sys.dm_pdw_request_steps (Transact-SQL)
sys.dm_pdw_request_steps Holds information about all steps that compose a given request or query in Azure Synapse Analytics.
WilliamDAssafMSFT
wiassaf
randolphwest
04/15/2024
sql
data-warehouse
reference
TSQL
>=aps-pdw-2016||=azure-sqldw-latest

sys.dm_pdw_request_steps (Transact-SQL)

[!INCLUDE applies-to-version/asa-pdw]

Holds information about all steps that compose a given request or query in [!INCLUDE ssazuresynapse-md]. It lists one row per query step.

Note

[!INCLUDE synapse-analytics-od-unsupported-syntax]

Column name Data type Description Range
request_id nvarchar(32) request_id and step_index make up the key for this view.

Unique numeric ID associated with the request.		 See request_id in sys.dm_pdw_exec_requests.
step_index int request_id and step_index make up the key for this view.

The position of this step in the sequence of steps that make up the request.		 0 to (n - 1) for a request with n steps.
plan_node_id int The node ID corresponding to the operator ID of that step in the execution plan. None
operation_type nvarchar(35) Type of operation represented by this step. DMS query plan operations: PartitionMoveOperation, MoveOperation, BroadcastMoveOperation, ShuffleMoveOperation, TrimMoveOperation, CopyOperation, DistributeReplicatedTableMoveOperation

SQL query plan operations: ReturnOperation, OnOperation, RemoteOperation

Other query plan operations: MetaDataCreateOperation, RandomIDOperation

External operations for reads: HadoopShuffleOperation, HadoopRoundRobinOperation, HadoopBroadcastOperation

External operations for MapReduce: HadoopJobOperation, HdfsDeleteOperation

External operations for writes: ExternalExportDistributedOperation, ExternalExportReplicatedOperation, ExternalExportControlOperation

For more information, see "Understanding Query Plans" in the [!INCLUDE pdw-product-documentation].

A query plan can also be affected by the database settings. Check ALTER DATABASE SET options for details.
distribution_type nvarchar(32) Type of distribution this step undergoes. AllNodes, AllDistributions, AllComputeNodes, ComputeNode, Distribution, SubsetNodes, SubsetDistributions, Unspecified
location_type nvarchar(32) Specifies where the step is running. Compute, Control, DMS
status nvarchar(32) Status of this step. Pending, Running, Complete, Failed, UndoFailed, PendingCancel, Cancelled, Undone, Aborted
error_id nvarchar(36) Unique ID of the error associated with this step, if any. NULL if no error occurred. The request_id can be matched with the request_id in sys.dm_pdw_errors to view all of the listed errors for that specific request_id.
start_time datetime Time at which the step started execution. Smaller or equal to current time and larger or equal to end_compile_time of the query to which this step belongs. For more information on queries, see sys.dm_pdw_exec_requests.
end_time datetime Time at which this step completed execution, was canceled, or failed. Smaller or equal to current time and larger or equal to start_time. Set to NULL for steps currently in execution or queued.
total_elapsed_time int Total amount of time the query step has been running, in milliseconds. Between 0 and the difference between end_time and start_time. 0 for queued steps.

If total_elapsed_time exceeds the maximum value for an integer, total_elapsed_time continues to be the maximum value. This condition generates the warning "The maximum value has been exceeded."

The maximum value in milliseconds is equivalent to 24.8 days.
row_count bigint Total number of rows changed or returned by this request. The number of rows affected by the step. Greater than or equal to zero for data operation steps. -1 for steps that don't operate on data.
estimated_rows bigint Total number of rows of work calculated during query compilation. The number of rows estimated by the step. Greater than or equal to zero for data operation steps. -1 for steps that don't operate on data.
command nvarchar(4000) Holds the full text of the command of this step. Any valid request string for a step. NULL when the operation is of the type MetaDataCreateOperation. Truncated if longer than 4,000 characters.

For information about the maximum rows retained by this view, see Capacity limits.

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