Check the hidden underscore parameters…

col "Parameter" FOR a50 col "Session Value" FOR a15 col "Instance Value" FOR a15 SELECT a.ksppinm "Parameter", b.ksppstvl "Session Value", c.ksppstvl "Instance Value" FROM x$ksppi a, x$ksppcv b, x$ksppsv c WHERE a.indx = b.indx AND a.indx = c.indx AND SUBSTR(ksppinm,1,1)=’_’ AND LOWER(a.ksppinm) LIKE LOWER(’%&param%’) ORDER BY a.ksppinm;

Setting the parameter:

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