* * * * *A Cron expression consists of 5 fields separated by whitespace, representing different units of time:
* * * * * - - - - - | | | | | | | | | +----- Day of Week (0 - 7) (Sunday=0 or 7) | | | +---------- Month (1 - 12) | | +--------------- Day of Month (1 - 31) | +-------------------- Hour (0 - 23) +------------------------- Minute (0 - 59)
0 * * * *Run once every hour at minute 0.
*/15 * * * *Run every 15 minutes.
0 0 * * 0Run once a week on Sunday at midnight.
0 9-17 * * 1-5Run every hour between 9am and 5pm, Monday to Friday.