查出数据库表中的comment

查表：

SELECT

  TABLE_NAME,

  TABLE_TYPE,

  COMMENTS

FROM

  USER_TAB_COMMENTS

WHERE

  TABLE_NAME = 'TD_PTL_OA_REQ_MSG'

  查字段：

  SELECT

  TABLE_NAME,

  COLUMN_NAME,

  COMMENTS

FROM

  USER_COL_COMMENTS

WHERE

  TABLE_NAME = 'TD_PTL_OA_REQ_MSG';