String consisting of six to seven fields that is separated by a space and represents a time.
Normally, a CRON expression is used to define routine jobs that are executed automatically at certain times by the system.
Fields
Seconds, mandatory field, valid value: 0-59, valid characters: *, /, , -.
Minutes, mandatory field, valid value: 0-59, valid characters: *, /, , -.
Hours, mandatory field, valid value: 0-59, valid characters: *, /, , -.
Day in month, mandatory field, valid value: 0-59, valid characters: *, /, , -.
Month, mandatory field, valid value: 0-12 or JAN-DEC, valid characters: *, /, , -.
Day of the week, mandatory field, valid value: 0-7 or SUN-SAT, valid characters: *, /, , -, ?, L, C, #.
Year, not a mandatory field, valid value: 1970-2010, valid characters: *, /, , -.