SELECT CHR(64+alpha) AS p
     , MIN(DECODE(rNum, 1, lotto)) AS n1
     , MIN(DECODE(rNum, 2, lotto)) AS n2
     , MIN(DECODE(rNum, 3, lotto)) AS n3
     , MIN(DECODE(rNum, 4, lotto)) AS n4
     , MIN(DECODE(rNum, 5, lotto)) AS n5
     , MIN(DECODE(rNum, 6, lotto)) AS n6
  FROM (SELECT alpha
             , lotto
             , ROW_NUMBER() OVER(PARTITION BY alpha ORDER BY lotto) rNum    -- 요기
          FROM (SELECT alpha
                     , lotto
                     , ROW_NUMBER() OVER(PARTITION BY alpha ORDER BY dbms_random.value) rNum
                  FROM (SELECT LEVEL alpha FROM dual CONNECT BY LEVEL <= 5)
                     , (SELECT LEVEL lotto FROM dual CONNECT BY LEVEL <= 45)
                -- ORDER BY alpha ASC, lotto ASC    -- 불필요.
                )
         WHERE rNum <= 6
        )
 GROUP BY alpha
 ORDER BY alpha    -- 필요.
;

혹시 rNum <=6 을안붙이면 LOTTO가 1부터 계속 찍히는데, 붙이니까 그제서야 랜덤값으로 다 찍히더라구요 

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