Script to find Dictionary Hit ratio, Library Cache Hit ratio & SQLs with high disk reads.

REM: Script for Dictionary Hit ratio
REM:*****************************************
REM: NOTE: PLEASE TEST THIS SCRIPT BEFORE USE.
REM: Author will not be responsible for any damage that may be cause by this script.
REM:*****************************************

SELECT (1 - (SUM (getmisses) / SUM (gets))) * 100 \"Hit Ratio\"
FROM v$rowcache;

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REM: Script for finding Library Cache Hit ratio
REM:*****************************************
REM: NOTE: PLEASE TEST THIS SCRIPT BEFORE USE.
REM: Author will not be responsible for any damage that may be cause by this script.
REM:*****************************************

SELECT SUM (pins) / (SUM (pins) - SUM (reloads)) * 100 \"Hit Ratio\"
FROM v$librarycache;

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REM: Script to find sql with high disk reads.
REM:*****************************************
REM: NOTE: PLEASE TEST THIS SCRIPT BEFORE USE.
REM: Author will not be responsible for any damage that may be cause by this script.
REM:*****************************************

SELECT disk_reads, sql_text
FROM v$sqlarea
WHERE disk_reads > 1000
ORDER BY disk_reads DESC;

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