테이블사이즈와 데이터사이즈를 확인해보고자 아래처럼 쿼리를 작성했습니다.
우선, 아래쿼리로 확인하면 되는게 맞는지 확인좀 부탁드리구요.

두번째는 테이블사이즈보다 데이터사이즈가 크게 보이는게 몇개 있습니다.
이게 분석시간차이에 따른 오차로 이렇게 보이는게 맞나요? (분석된 후 DATA가 변경되서..)

SELECT GUBUN "구분"
     , ROW_NUMBER() OVER(ORDER BY GUBUN DESC, SIZE2 DESC) "NO"
     , SEG_NAME "세그먼트명"
     , NUM_ROWS "데이터건수(근사치)"
     , SIZE2 "SEGMENT크기(byte)"
     , SIZE1 "DATA크기(byte)"
     , CASE WHEN SIZE2 <= 1024       THEN SUBSTR('      '||SIZE2||' BYTE',-10)
            WHEN SIZE2 <= 1024000    AND SIZE2 > 1024    THEN SUBSTR('      '||ROUND(SIZE2/1024,1)||' KB',-10)
            WHEN SIZE2 <= 1024000000 AND SIZE2 > 1024000 THEN SUBSTR('      '||ROUND(SIZE2/1024/1024,1)||' MB',-10)
            ELSE SUBSTR('      '||ROUND(SIZE2/1024/1024/1024,1)||' GB',-10) END "SEGMENT크기"
     , CASE WHEN SIZE1 <= 1024       THEN SUBSTR('      '||SIZE1||' BYTE',-10)
            WHEN SIZE1 <= 1024000    AND SIZE1 > 1024    THEN SUBSTR('      '||ROUND(SIZE1/1024,1)||' KB',-10)
            WHEN SIZE1 <= 1024000000 AND SIZE1 > 1024000 THEN SUBSTR('      '||ROUND(SIZE1/1024/1024,1)||' MB',-10)
            ELSE SUBSTR('      '||ROUND(SIZE1/1024/1024/1024,1)||' GB',-10) END "Data크기(근사치)"
     , CASE WHEN INIT_SIZE <= 1024       THEN SUBSTR('      '||INIT_SIZE||' BYTE',-10)
            WHEN INIT_SIZE <= 1024000    AND INIT_SIZE > 1024    THEN SUBSTR('      '||ROUND(INIT_SIZE/1024,1)||' KB',-10)
            WHEN INIT_SIZE <= 1024000000 AND INIT_SIZE > 1024000 THEN SUBSTR('      '||ROUND(INIT_SIZE/1024/1024,1)||' MB',-10)
            ELSE SUBSTR('      '||ROUND(INIT_SIZE/1024/1024/1024,1)||' GB',-10) END "초기크기"
     , CASE WHEN NEXT_SIZE <= 1024       THEN SUBSTR('      '||NEXT_SIZE||' BYTE',-10)
            WHEN NEXT_SIZE <= 1024000    AND NEXT_SIZE > 1024    THEN SUBSTR('      '||ROUND(NEXT_SIZE/1024,1)||' KB',-10)
            WHEN NEXT_SIZE <= 1024000000 AND NEXT_SIZE > 1024000 THEN SUBSTR('      '||ROUND(NEXT_SIZE/1024/1024,1)||' MB',-10)
            ELSE SUBSTR('      '||ROUND(NEXT_SIZE/1024/1024/1024,1)||' GB',-10) END "확장크기"
     , CASE WHEN MAX_SIZE <= 1024       THEN SUBSTR('      '||MAX_SIZE||' BYTE',-10)
            WHEN MAX_SIZE <= 1024000    AND MAX_SIZE > 1024    THEN SUBSTR('      '||ROUND(MAX_SIZE/1024,1)||' KB',-10)
            WHEN MAX_SIZE <= 1024000000 AND MAX_SIZE > 1024000 THEN SUBSTR('      '||ROUND(MAX_SIZE/1024/1024,1)||' MB',-10)
            ELSE SUBSTR('      '||ROUND(MAX_SIZE/1024/1024/1024,1)||' GB',-10) END "제한크기"
     , SIZE2 - SIZE1 "낭비공간(byte)"
     , CASE WHEN (SIZE2 - SIZE1) <= 1024       THEN SUBSTR('      '||(SIZE2 - SIZE1)||' BYTE',-10)
            WHEN (SIZE2 - SIZE1) <= 1024000    AND (SIZE2 - SIZE1) > 1024    THEN SUBSTR('      '||ROUND((SIZE2 - SIZE1)/1024,1)||' KB',-10)
            WHEN (SIZE2 - SIZE1) <= 1024000000 AND (SIZE2 - SIZE1) > 1024000 THEN SUBSTR('      '||ROUND((SIZE2 - SIZE1)/1024/1024,1)||' MB',-10)
            ELSE SUBSTR('      '||ROUND((SIZE2 - SIZE1)/1024/1024/1024,1)||' GB',-10) END "낭비공간"
     , LAST_ANALYZED "분석된시간"
FROM (
      SELECT B.SEGMENT_TYPE GUBUN
           , A.TABLE_NAME SEG_NAME
           , A.NUM_ROWS
           , DECODE(A.AVG_ROW_LEN,0,0,GREATEST(4,CEIL(A.NUM_ROWS/((ROUND(((1958-(A.INI_TRANS*23))*((100-A.PCT_FREE)/100))/A.AVG_ROW_LEN))))*2048)) SIZE1 --데이터사이즈
           , B.BYTES SIZE2 -- TABLE사이즈
           , A.INITIAL_EXTENT INIT_SIZE
           , A.NEXT_EXTENT    NEXT_SIZE
           , A.MAX_EXTENTS    MAX_SIZE
           , A.LAST_ANALYZED
        FROM USER_TABLES   A
           , USER_SEGMENTS B
       WHERE 1 = 1
         AND A.TABLE_NAME = B.SEGMENT_NAME
         AND B.SEGMENT_TYPE = 'TABLE'
       UNION ALL
      SELECT B.SEGMENT_TYPE GUBUN
           , A.INDEX_NAME SEG_NAME
           , A.NUM_ROWS
           , NULL    SIZE1 -- 데이터사이즈
           , B.BYTES SIZE2 -- INDEX사이즈
           , A.INITIAL_EXTENT INIT_SIZE
           , A.NEXT_EXTENT    NEXT_SIZE
           , A.MAX_EXTENTS    MAX_SIZE
           , A.LAST_ANALYZED
        FROM USER_INDEXES  A
           , USER_SEGMENTS B
      WHERE A.INDEX_NAME = B.SEGMENT_NAME
        AND B.SEGMENT_TYPE = 'INDEX'
) ORDER BY 1 DESC, 5 DESC
;