RE: CHAIN Versus SETLL and READ When Data Needed

["Sharon Wintermute" <SWintermute@xxxxxxxxxxxx>]

Shannon, 

I have come to the point where i nearly HATE if with nested else groups. 
I have started going this route.

DOU (wExit = Yes);
        SETLL all three
        if %Equal;
           Leave;
        Endif   ;
        SETLL 2 keys
        if %Equal;
          Leave;
        Endif;
        setll 1 key

        Leave;
Enddo;

This way i always have the status
If I need to know which file I add a flag. 

wExit is never set anywhere in the routine.  Its only used as a way to loop.


Sharon



>    The program logic is such that you check the maximum number of keys
> for a match down to the minimum number of keys
>
>
>
>     Like this:
>
>
>
>              Key1    Klist
>
>                          Kfld              Fld1
>
>                          Kfld              Fld2
>
>                          Kfld              Fld3
>
>
>
>              Key2     Klist
>
>                          Kfld              Fld1
>
>                          Kfld              Fld2
>
>
>
>              Key3     Klist
>
>                           Kfld             Fld1
>
>
>
>
>
>   Which one of these logic blocks is most efficient?
>
>
>
>   Key1   Setll   file
>
>       If    %FOUND(file)
>
>               Key1   READE file
>
>                       Use Fields
>
>       Else
>
>          Key2    Setll  File
>
>            If   %FOUND(file)
>
>                     Key2 Use Fields
>
>           Else
>
>             Key3  Setll File
>
>                  If   %FOUND(file)
>
>                     Key3 READE file
>
>               Endif
>
>            Endif
>
>          Endif
>
>
>
>
>
>
>
> OR....
>
>
>
>               KEY1  Chain file
>
>                          If       %FOUND(file)
>
>                              Use fields
>
>                         Else
>
>              KEY2   Chain  file
>
>                          If      %FOUND(file)
>
>                              Use Fields
>
>                          Else
>
>              KEY3   Chain file
>
>                          If   %FOUND(file)
>
>                             Use Fields
>
>                         Endif
>
>                         Endif
>
>                         Endif
>
>
>
>
>
> My opinion is that the CHAIN is more efficient from both a
> coding/maintenance standpoint and from an I/O standpoint, but I'm open
> to opinions.
>
>
>
>
>
>
>
>
>
>
>
> -- 
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