Home Forums SQL Server 2005 SQL Server 2005 General Discussion Moving Average Over a Data Table Requiring Group RE: Moving Average Over a Data Table Requiring Group

  • December 8, 2008 at 9:39 am

    #909227

    Or better still:

    UPDATE a SET Avg1WkVol = (SELECT AVG(Volume) from Test_HistoricalData b where b.Symbol = a.Symbol AND b.MarketDate a.MarketDate-8)

    FROM Test_HistoricalData a

    Although the previous version is much easier to disassemble for testing.

    “Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw

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