r will result in no change
     in the planner's choices.  By default, these cost variables are based on
     the cost of sequential page fetches; that is,
     <TT
CLASS="VARNAME"
>seq_page_cost</TT
> is conventionally set to <TT
CLASS="LITERAL"
>1.0</TT
>
     and the other cost variables are set with reference to that.  But
     you can use a different scale if you prefer, such as actual execution
     times in milliseconds on a particular machine.
    </P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P