The query will have the controlling thread(1) |--Stream Aggregate(GROUP BY:([ORDERS].[o_orderpriority]) DEFINE:([Expr1005]=COUNT(*))) |--Parallelism(Gather Streams, ORDER BY:([ORDERS].[o_orderpriority] ASC))(1 input and 2 output)|--Stream Aggregate(GROUP BY: ([ORDERS].[o_orderp...
SQL Server 2005 Analyzing a Query Logical and Physical Operators Reference Add Add to Collections Add to plan Share via Facebookx.comLinkedInEmail Print Article 03/12/2008 TheParallelismoperator performs the distribute streams, gather streams, and repartition streams logical operations. TheArgumentcolumn...
When a query uses a single partition e.g. all but a single partition is eliminated, SQL Server 2005 Intra-Partition parallelism can parallelize row retrieval using multiple threads up to the sp_configure’d value of Maximum Degree of Parallelism (MAXDOP). Frequently, MAXDOP is se...
如果查询被编译成并行查询,但在运行时作为串行查询运行,则由 SET STATISTICS XML 或通过使用 SQL Server Management Studio 中的“包括实际的执行计划”选项生成的显示计划输出将不包含Parallelism运算符的 RunTimeInformation 元素。在 SET STATISTICS PROFILE 输出中,为Parallelism运算符显示的实际行计数和实际执行数将为...
Distribute Streams 1 DOPA gather streams exchange is often called a “start parallelism” exchange since the operators above it run serially while the operators below it run in parallel. The root exchange in any parallel plan is always a gather exchange since the results of any query plan must...
A merging exchange only make sense for a gather or a repartition streams exchange; with a distribute streams exchange, there is only one producer and, thus, only one stream of rows and nothing to merge at each consumer. Showplan SQL Server includes all of the above properties in showplan (...
A merging exchange only make sense for a gather or a repartition streams exchange; with a distribute streams exchange, there is only one producer and, thus, only one stream of rows and nothing to merge at each consumer. Showplan SQL Server includes all of the above properties in showplan (...
\n |--Parallelism(Gather Streams)\n \n \n \n \n \n \n \n 2\n \n \n \n \n \n\n \n \n 12\n \n \n \n \n \n \n \n \n \n SELECT …. WHERE DateCol BETWEEN ’10/1/2005’ and ‘11/30/2005’\n \n\n ...
Repartition Streams Showplan Operator Gather Streams Showplan Operator Concepts Logical and Physical Operators Reference Displaying Execution Plans by Using the Showplan SET Options (Transact-SQL) Help and Information Getting SQL Server 2005 Assistance...
Repartition Streams Showplan Operator Gather Streams Showplan Operator Concepts Logical and Physical Operators Reference Displaying Execution Plans by Using the Showplan SET Options (Transact-SQL) Help and Information Getting SQL Server 2005 Assistance...