Microsoft® SQL Server 2012 Unleashed

Identifying Parallel Queries

You can identify when a parallel execution plan is being chosen by displaying the graphical execution plan in SSMS. The graphical execution plan uses icons to represent the execution of specific statements and queries in SQL Server. The execution plan output for every parallel query has at least one of these three logical operators:

Distribute Streams—Receives a single input stream of records and distributes multiple output streams. The contents and form of the record are unchanged. All records enter through the same single input stream and appear in one of the output streams, preserving the relative order.

Gather ...