oracle and mysql traverse each day of the current month

Get every day of the current month's data

oracle

SELECT TO_DATE(TO_CHAR(SYSDATE, 'YYYYMM'), 'YYYYMM') + (ROWNUM - 1) DAY_ID
  FROM DUAL
CONNECT BY ROWNUM <=
           TO_NUMBER(TO_CHAR(LAST_DAY(TO_DATE(TO_CHAR(SYSDATE, 'YYYYMM'),
                                              'YYYYMM')),
                             'DD'))

mysql

SELECT
  DATE_ADD(CURDATE(),INTERVAL(CAST(help_topic_id AS SIGNED INTEGER)-(DAYOFMONTH(CURDATE())-1)) DAY) DAY
FROM mysql.help_topic
WHERE help_topic_id < DAY(LAST_DAY(CURDATE()))
ORDER BY help_topic_id

Note: help_topic mysql table stored in the built-in functions

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