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摘要： Aggregation Aggregation refers to the collapse of a larger set of rows into a smaller set of rows. Typical aggregate functions are COUNT, MIN, MAX, SUM, and AVG. SQL Server also supports other aggr... 阅读全文

摘要： Stream Aggregate There are two physical operators that SQL Server uses to compute general purpose aggregates where we have a GROUP BY clause. One of these operators is stream aggregate which as we sa... 阅读全文