How do I fetch specific record from a given sas dataset

[VVDR]

Hi,

From a given SAS Dataset, how can I fetch last but one record or third record from the last without doing hard coding. I don't want to do hard coding the values as the number of observations keep on changing. 

TIA.

[novinosrin · Accepted solution]

Hi @VVDR  Using SASHELP.CLASS dataset that has 19 records, here is an illustration-

The comments should make sense to you

/*last but one=numofrecs-1,third=last minus 2 records*/

data want;
/*last but one=numofrecs-1,third=last minus 2 records*/
 do _n_= nobs-1, nobs-2;
  set sashelp.class nobs=nobs point=_n_;
  output;
 end;
 stop;
run;

[Patrick]

Are these assignment questions?

Here one way to get what the question asked for. The code below selects the 3rd last column.

%let n_obs_from_last=3;
data want;
  obs=nobs -&n_obs_from_last +1;
  if obs>0 then
    do;
      set sashelp.class nobs=nobs point=obs;
      output;
    end;
  stop;
run;

[Reeza]

SAS supports indexing to allow for efficient data retrieval. If you need to extract records by varying criteria you may want to add in some indexes to support your queries.