RESET variable
Refer to the SET statement for more information on available variables.
Message returned if variable is successfully reset to its default value..
RESET restores variables to the default values. Refer to the SET command for details on allowed values and defaults. RESET is an alternate form for SET variable = DEFAULT
The RESET statement is a Postgres language extension.
Refer to SET/SHOW statements to set/show variable values.
Set DateStyle to its default value:
RESET DateStyle;
Set Geqo to its default value:
RESET GEQO;
There is no RESET in SQL92.