testing previous table (changeing values)

[ger15xxhcker]

There is a table with a uniqe ID. This is an external time stamp table (yymmdd).I'd like to check if a fields (in the previous month) A colums, B columns and C columns have changed on the same ID in this table then we will update field  in the new table e.g: D:='Y'. If the table does not exist then do not nothing.

Thanks!

[Kurt_Bremser]

Run a proc compare in a

%if %sysfunc(exist(datasetname)) %then %do;

%end;

block.

[ger15xxhcker]

Thanks, but how can i define a column value to the new dataset based on these result? I shows the diff but how can i use it to in a data set to add the flg value to 'Y'

e.g:

data have190430;
input ID	(Startdate Enddate)(:date11.)	Name $ Flg $;
format Startdate Enddate date11.;
datalines;
1	26-Sep-13	26-Sep-13	Erloti    n
2	23-Oct-13	23-Oct-13	AAAAAA    n
3	22-Nov-13	22-Nov-13	Erloti    n
4	16-Dec-13	16-Dec-13	Erloti    n
;
run;

data have190331;
input ID	(Startdate Enddate)(:date11.)	Name $ Flg $;
format Startdate Enddate date11.;
datalines;
1	26-Sep-13	26-Sep-13	Erloti    n
2	23-Oct-13	23-Oct-13	Erloti    y
3	22-Nov-13	22-Nov-13	Erloti    n
4	16-Dec-13	16-Dec-13	Erloti    n
;
run;

[Kurt_Bremser · Accepted solution]

You can use a data step update:

data new;
update
  have190430
  have190331
;
by id startdate enddate;
run;