Please a parameter to disable undo, like _disable_logging

Hi, I searched but I didn't find it, please do you know some parameter like _disable_logging (disables logging),
to disable undo.

SELECT KSPPINM, KSPPSTVL
FROM X$KSPPI A, X$KSPPSV B
WHERE A.INDX=B.INDX AND SUBSTR(KSPPINM,1,1) = '_' and upper(KSPPINM) like '%UNDO%' ;  

This is only to speed my test database, thanks.  

Juan Carlos Reyes Pacheco
OCP

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