data A_TABELA;
input A_PK;
datalines;
11
12
13
14
15
.
;
run;
 
data B_TABELA;
input B_PK;
datalines;
12
13
.
15
;
run;
 
/* DISTINCT gives incorrect row count. Expected 2 rows */

PROC SQL feedback;
     CREATE TABLE ZAPYTANIE1 AS 
     SELECT DISTINCT CZY_W_B_TABELI FROM 
     (select DISTINCT A_PK, 1 as CZY_W_A_TABELI from A_TABELA WHERE A_PK NOT IS NULL) as a
     FULL JOIN 
     (select DISTINCT B_PK, 1 as CZY_W_B_TABELI from B_TABELA WHERE B_PK NOT IS NULL) as b
     on a.A_PK = b.B_PK
;
QUIT;

  
/* COUNT() gives incorrect row count. Expected 2 rows */
 
PROC SQL feedback;
     CREATE TABLE ZAPYTANIE2 AS 
     SELECT CZY_W_B_TABELI,COUNT(*) AS ILE  FROM 
     (select DISTINCT A_PK, 1 as CZY_W_A_TABELI from A_TABELA WHERE A_PK NOT IS NULL) as a
     FULL JOIN 
     (select DISTINCT B_PK, 1 as CZY_W_B_TABELI from B_TABELA WHERE B_PK NOT IS NULL) as b
     on a.A_PK = b.B_PK
     GROUP BY CZY_W_B_TABELI
;
QUIT;