SELECT
  CASE FLOOR_LINE_ID
    WHEN 1
    THEN '高铁'
    WHEN 2
    THEN '高速'
    WHEN 3
    THEN '公路'
    WHEN 5
    THEN '地铁'
    ELSE '其他'
  END AS LINE_NAME,
  FLOOR_LINE_ID
FROM
  ( SELECT FLOOR(LINE_ID/100) AS FLOOR_LINE_ID FROM DT4_LINE_NAME
  )

改为

SELECT LINE_ID,
  DECODE(FLOOR(LINE_ID/100),1,'高铁',2,'高速',3,'公路',5,'地铁',6,'公交') AS LINE_NAME
FROM DT4_LINE_NAME