Rows|Range enhances partition functionality of Over clause in SQL Server 2012. In the Over clause before SQL 2012, you can group rows with the same attributes together, which is called partition. You can also order the rows within each of partitions, which is implemented by Order By. The aggregation functions in front of Over clause will be are partition and order based. In SQL Server 2012, a lower level “partition”, which is called windows fram, range of rows, can be defined under the partition. A window frame can be static like partition clause but can also be dynamic – moving window. This provides great power on data analytics, for instance, you no longer need joins for calculating moving average, instead, one SQL with moving window can give you the result.

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