Report on SQL Server's plan cache history over time.

PlanCacheByDateAndHour.sql

/* 
SQL Server Plan Cache History by Date & Time
Brent Ozar, 2018/07/03 - https://BrentOzar.com/go/plansbydate

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Anyone is free to copy, modify, publish, use, compile, sell, or
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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*/


SELECT TOP 50
    creation_date = CAST(creation_time AS date),
    creation_hour = CASE
                        WHEN CAST(creation_time AS date) <> CAST(GETDATE() AS date) THEN 0
                        ELSE DATEPART(hh, creation_time)
                    END,
    SUM(1) AS plans
FROM sys.dm_exec_query_stats
GROUP BY CAST(creation_time AS date),
         CASE
             WHEN CAST(creation_time AS date) <> CAST(GETDATE() AS date) THEN 0
             ELSE DATEPART(hh, creation_time)
         END
ORDER BY 1 DESC, 2 DESC;
GO