SQL查询返回与当前日期或当月最后一天匹配的行

Question

I have a scheduler application in php that runs actions at certain days of the month based on information stored in a "schedules" table. Each row is a separate action and one of the columns stores the day of the month to use for scheduling. The application executes actions every day by cron job. The problem I have is if someone defines a schedule to run on the 31st of every month.

This is the query that I am currently using to get the schedules to run for the current day:

SELECT * FROM schedules WHERE dayOfTheMonth = DAY(CURDATE())

This won't work for months that don't have 31 days but I want to make sure the schedule runs monthly. So it should run on the last day of the month if the stored day exceeds the last day for this month. Does anyone know an elegant way to do this?

Answer 1

SELECT
    *
FROM
    schedules
WHERE
    (
        DAY( CURDATE() ) = DAY( LAST_DAY( CURDATE() ) )
        AND
        dayOfTheMonth > DAY( LAST_DAY( CURDATE() ) )
    )
    OR
    dayOfTheMonth = DAY( CURDATE() )

If the current day is the last day of the month (eg Feb 28), then any schedule set on a day after the 28th (eg 29, 30, 31) will also be selected and returned - otherwise it only matches rows that have an exact day match.