cron reference

Cron expression is

how many characters a string consists of. Each system and environment are different. Some cannot be accurate to the second
but can be identified by the ? sign, "day, month and week", only "day" and A question mark can be used for "week". The

shortcut is a question mark sandwiched with "month",
such as 13 13 15 20 *?
At a glance, you can see that the question mark is a week, executed every month, and on the 20th of each month. Then 13 13 15 can be seen at a glance .


Usually, "Sun, Moon and Week" is preceded by "Seconds and Hours".

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Attachment:
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This URL can parse cron
https://cronexpressiondescriptor.azurewebsites.net/?expression=0+15+10+%3F+*+6L++2002-2006&locale=zh-CN 2Reference

link
http
:// www.cnblogs.com/linjiqin/archive/2013/07/08/3178452.html
http://jingyan.baidu.com/article/7f41ecec0d0724593d095c19.html
http://www.blogjava.net/hao446tian/archive/2012/ 02/13/369872.html
http://infocenter.sybase.com/help/index.jsp?topic=/com.sybase.infocenter.dc01963.0510/doc/html/psh1360346725201.html