If you need to display in your worksheet, you may use dbms_output.put_line
make necessary changes in the procedure to display:
create OR REPLACE
PROCEDURE display(
p IN VARCHAR2)
AS
pur_dis purchase%rowtype;
sal_dis sales%rowtype;
BEGIN
SELECT * INTO pur_dis FROM purchase WHERE proid=p;
dbms_output.put_line('Displaying your values:'||pur_dis.Purid||' '||pur_dis.Proid||' '||pur_dis.qty||' '||pur_dis.supname);
SELECT * INTO sal_dis FROM sales WHERE proid=p;
END;
/
call the procedure:
SET SERVEROUTPUT ON
begin
display(value_of_p);
end;
/