output if a subject or site or visit or date is missing

[Vijay77]

Hi ,

i have a scenario to

Output If the Site or Subject or Visit number or Visit Date is either present in the "A" data set but is missing from the "B" data set or vice versa?

any suggestions will be helpful, Thanks.

[Jagadishkatam]

You can use the merge statement with by group to output such records or else you can also use the proc sql joins.

An example data would help to get better inputs.

[Vijay77]

Hi,

consider these as a example data

A                                                                                                             B

site  subject  Visit number Visit Date                                         site  subject  Visit number Visit Date

101 123        10                  12aug2019                                     101   123        15                12aug2019  *here visit number diff so i should get as missing visnumber

101 134         05                 14aug2019                                     101   134        05                 .                   *here output missing date from b

101 135        09                     .                                                   101   135        09                 14aug2019  *here output missing date from a

[Jagadishkatam]

please try the below code

proc sort data=dataset_a;
by site subject visit_number visit_date;
run;

proc sort data=dataset_b;
by site subject visit_number visit_date;
run;

data want;
merge dataset_a(in=a) dataset_b(in=b);
by site subject visit_number visit_date;
if b and not a;
run;

[Shmuel · Accepted solution]

As @Vijay77 asked for: "...present in the "A" data set but is missing from the "B" data set or vice versa?"

a light change need to last step of @Jagadishkatam :

data want;
merge dataset_a(in=a) dataset_b(in=b);
by site subject visit_number visit_date;
if not (a and b);   /* line changed */
run;

[Vijay77]

Will this work for missing dates from either A or B with same site subject and visit

[Shmuel]

Yes. of course. The checking is done after merging. 

[Vijay77]

for missing dates:
merge a(in=x) b(in=y);
by site subjid visit;
if (x and y);
if missing(vis_date); run;