Hidden initialization parameters
It seemd that the number of hidden parameters is increasing between versions. a small check reveals that: version 8.1.7.4 contains 300 paramters. version 9.2.0.8 contains 613 paramters. version 10.2.0.3 contains 1179 paramters. Here is the query I used to locate these parameters: SELECT a.ksppinm "Parameter", a.ksppdesc "Description", 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 a.ksppinm LIKE '/_%' escape '/';