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    Cron

    Cron

    A CRON expression is simply a string consisting of six fields that each define a specific unit of time. 

    They are written in the following format:

    {second} {minute} {hour} {day} {month} {day of the week}

    Values

    The following values are allowed within each date/time unit placeholder.

    FieldAllowed Values Description
    {second}0-59Trigger every {second} second(s)
    {minute}0-59Trigger every {minute} minute(s)
    {hour}0-23Trigger every {hour} hour(s)
    {day}1-31Trigger every {day} day(s) of month
    {month}1-12Trigger every {month} month(s)
    {day of week}0-6MON-SUN Trigger on specific {day of week}

    Special Characters

    Additionally you can also use the following special characters to build more advanced expressions:

    Special CharacterDescription
    *Trigger on tick of every time unit
    ,List separator
    –Specifies a range
    /Defines an increment

    Examples

    0 * * * * * - Executes every minute
    0 0 * * * * - Executes every hour
    0 0 0 * * * - Executes every day
    0 0 0 0 * * - Executes every month
    0 0 0 1 1 * - Executes on first day of Jan each year
    30 20 * * SAT - Executes at 08:30pm every Saturday
    30 20 * * 6 - Executes at 08:30pm every Saturday
    0 */5 * * * * - Executes every five minutes
    0 0 8-10/1 * * * - Executes every hour between 8am and 10am

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