Connaître la taille du cache alloué aux bases de données d’une instance

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-- Nicolas SOUQUET - 09/02/2011
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SELECT    CASE
      WHEN GROUPING(D.name) = 1 THEN 'TOTAL'
      ELSE D.name  
    END AS database_name
    , CAST(COUNT_BIG(*) / 128.0 AS decimal(10,2)) AS cached_size_MB
FROM    sys.dm_os_buffer_descriptors AS OSBD
INNER JOIN  sys.databases AS D ON OSBD.database_id = D.database_id
--WHERE    D.name = 'maBD'
GROUP BY  D.name WITH ROLLUP
ORDER BY  cached_size_MB DESC