Compare two data sets

[Rohan]

Hello Friends,

I want to search if a observation (date) in data set B1 is in data set A1 or not.

If obv in A1 found then print "found" else append the observation of B1 into A1.

data a1;

input date_file $;

datalines;

24NOV2011

25NOV2011

26NOV2011

27NOV2011

28NOV2011

;

data b1;

input date_file $;

datalines;

26NOV2011

30NOV2011

;

I try to use PROC COMPARE but it's not giving desirable result. Please help me out.

Thanks

Rohan,

[Haikuo]

Assume they are both sorted, then we can have:

data a1;

merge a1(in=a) b1(in=b);

by date_file;

if a then output;

if a and b then put "Found=" date_file;

else if b and not a then output;

run;

Regards,

Haikuo

[VijayNair]

I Have to create datasets with sysmonth, sysmonth-1 & Sysmonth-2 as the names, how can i do that?

[art297]

Vijay, Since your screen name is different than the original poster's name, I'd suggest that you start a new discussion, provide an example "have" data set and an example "want" dataset.

[Linlin]

show off my newly acquired hash skills:

data a1;

input date_file $;

datalines;

24NOV2011

25NOV2011

26NOV2011

27NOV2011

28NOV2011

;

data b1;

input date_file $;

datalines;

26NOV2011

30NOV2011

;

data _null_;

  if _n_=1 then do;

  declare hash ha(dataset:'b1', ordered: 'yes');

    ha.definekey('date_file');

          ha.definedata('date_file');

          ha.definedone();

  end;

          set a1 ;

          rc=ha.find();

          if rc = 0 then put "Found=" date_file;

          else ha.add();

  ha.output(dataset:'ai_updated');

run;

Linlin