How to debug SAS code using Data Step Debuger

Debug Command:
data xxx / debug
go -- until break 7
step = return
examine _all_
quit
set
                break point:

/*  =----------- debug examples -------
http://support.sas.com/documentation/cdl/en/lrdict/64316/HTML/default/viewer.htm#a000379345.htm
*/

/* debug example: first execution */
data tours (drop=type) ; * / debug;
retain Tour; /* add retain to keep the data */
input @1 type $ @;
    if type='H' then
      do;
     input @3 Tour $20.;
     return;
      end;
   else if type='P' then
 do;
     input @3 Name $10. Age 2. +1 Sex $1.;
     output;
      end;
   datalines;
H Tour 101
P Mary E    21 F
P George S  45 M
P Susan K    3 F
H Tour 102
P Adelle S  79 M
P Walter P  55 M
P Fran I    63 F
;
run;
proc print data=tours;
   title 'Tour List';
run;



/*  =----------- debug example 2 -------*/
options yearcutoff=1920;

data tours / debug;
  length Country $ 10;
  input Country $10. Start : mmddyy. End : mmddyy.;
  Duration=end-start;
datalines;
Italy       033000 041300
Brazil      021900 022800
Japan       052200 061500
Venezuela   110300 11800
Australia   122100 011501
;

proc print data=tours;
   format start end date9.;
   title 'Tour Duration';
run;

/* in debug: show output, then

1. break lineNo when country="Venezuela" --- break at error point

2. examine the date var: examine start date7.  | examine start mmddyy.

3. set start='18Nov00'd

Debugger Commands:

http://www.sfu.ca/sasdoc/sashtml/lgref/z0379386.htm

-------------

BREAK lineNo ; breake 4 when strVar=''; break 4 when numVar=value; 

break 4 after numberOf_Loop

JUMP lineNo

DELETE break lineNo

SET var=Value, when debug, can set some value for debug purpose

ENTER = step

STEP  = excute a statement, step forward

EXAMINE varName, _ALL_

GO lineNo.

QUIT

CALCULATE expression

LIST

DESCRIBE

SWAP

TRACE

HELP

WATCH

*/

/*  =----------- debug example 3 -------*/

/* break 331 after 5(loop repeat counts) */

data old;

input oldtest @@;

datalines;

2 3 3 4 4 4 5 5

;

run;

data new / debug;

   set old;

   do i=1 to 20;

      newtest=oldtest+i;

      output;

   end;

run;