RESET variable
Refer to SET for more information on available variables.
Message returned if variable is successfully reset to its default value.
RESET restores variables to their default values. Refer to SET for details on allowed values and defaults. RESET is an alternate form for
SET variable = DEFAULT
Set DateStyle to its default value:
RESET DateStyle;
Set Geqo to its default value:
RESET GEQO;
There is no RESET in SQL92.