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sys.dm_exec_distributed_requests (Transact-SQL)

Applies to: SQL Server 2016 (13.x) and later versions

Holds information about all requests currently or recently active in PolyBase queries. It lists one row per request/query.

Based on session and request ID, a user can then retrieve the actual distributed requests generated to be executed - via sys.dm_exec_distributed_requests. For example, a query involving regular SQL and external SQL tables will be decomposed into various statements/requests executed across the various compute nodes. To track the distributed steps across all compute nodes, we introduce a 'global' execution ID which can be used to track all operations on the compute nodes associated with one particular request and operator, respectively.

Column Name Data Type Description Range
sql_handle varbinary(64) Key for this view. Unique numeric id associated with the request. Unique across all requests in the system.
execution_id nvarchar(32 Unique numeric id associated with the session in which this query was run.
status nvarchar(32 Current status of the request. 'Pending', 'Authorizing', 'AcquireSystemResources', 'Initializing', 'Plan', 'Parsing', 'AcquireResources', 'Running', 'Cancelling', 'Complete', 'Failed', 'Cancelled'.
error_id nvarchar(36) Unique id of the error associated with the request, if any. Set to NULL if no error occurred.
start_time datetime Time at which the request execution was started. 0 for queued requests; otherwise, valid datetime smaller or equal to current time.
end_time datetime Time at which the engine completed compiling the request. NULL for queued or active requests; otherwise, a valid datetime smaller or equal to current time.
total_elapsed_time int Time elapsed in execution since the request was started, in milliseconds. Between 0 and the difference between start_time and end_time.If total_elapsed_time exceeds the maximum value for an integer, total_elapsed_time will continue to be the maximum value. This condition will generate the warning "The maximum value has been exceeded." The maximum value in milliseconds is equivalent to 24.8 days.

See Also

PolyBase troubleshooting with dynamic management views
Dynamic Management Views and Functions (Transact-SQL)
Database Related Dynamic Management Views (Transact-SQL)