Cron expressions-AnalyticDB(AnalyticDB)-阿里云帮助中心

AnalyticDB for PostgreSQL uses cron expressions to schedule periodic plans. A cron expression is a space-separated string of six or seven fields:

second minute hour day month week [year]

The Year field is optional. Each field accepts specific values or wildcard characters. When a field contains multiple values, separate them with commas (,).

Field values

Field	Required	Valid values	Supported wildcards
Second	Yes	0–59	`*` `,` `-` `/`
Minute	Yes	0–59	`*` `,` `-` `/`
Hour	Yes	0–23	`*` `,` `-` `/`
Day	Yes	1–31	`*` `,` `-` `/` `?` `L` `W`
Month	Yes	1–12 or JAN–DEC	`*` `,` `-` `/`
Week	Yes	1–7 or MON–SUN (1 = Monday, 7 = Sunday)	`*` `,` `-` `/` `?` `L` `#`
Year	No	1970–2099	`*` `,` `-` `/`

Wildcards

Wildcard	Description	Example	When triggered
`*`	Matches all values in the field.	`*` in Month	Every month
`,`	Specifies multiple discrete values.	`5,20` in Minute	At minutes 5 and 20 of each hour
`-`	Specifies a range of values.	`5-20` in Minute	Once every minute from minute 5 through minute 20
`/`	Specifies an increment. The value before `/` is the start; the value after is the step.	`0/15` in Minute	Every 15 minutes starting from minute 0 (at :00, :15, :30, :45)
		`3/20` in Minute	Every 20 minutes starting from minute 3
`?`	No value. Only supported in the Day and Week fields. When you set a specific value in one of these fields, set the other to `?` to avoid conflicts.	`?` in Week when Day is `15`	Matches any day of the week
`L`	The last day. Only supported in the Day and Week fields. Do not combine `L` with a list or range.	`L` in Day	The last day of the month
		`L` in Week	Sunday (the last day of the week)
		`6L` in Week	The last Saturday of the month
`W`	The nearest business day to the specified date, within the same month. Only supported in the Day field. `LW` matches the last business day of the month.	`5W` in Day	If the 5th is Saturday: Friday (4th). If Sunday: Monday (6th). If Mon–Fri: the 5th.
`#`	A specific weekday occurrence in the month. Only supported in the Week field.	`4#2` in Week	The second Thursday of the month

Examples

Important

Cron expressions use UTC. Convert your local time to UTC before writing an expression.

Scenario	UTC expression	UTC+8 expression
At 10:15 every day	`0 15 10 ? * *`	`0 15 18 ? * *`
At 10:15 every day	`0 15 10 * * ?`	`0 15 18 * * ?`
At 12:00 every day	`0 0 12 * * ?`	`0 0 20 * * ?`
At 10:00, 14:00, and 16:00 every day	`0 0 10,14,16 * * ?`	`0 0 18,22,0 * * ?`
Every 30 minutes from 09:00 to 17:00 every day	`0 0/30 9-17 * * ?`	`0 0/30 17-2 * * ?`
Every minute from 14:00 to 14:59 every day	`0 * 14 * * ?`	`0 * 22 * * ?`
Every minute from 14:00 to 14:05 every day	`0 0-5 14 * * ?`	`0 0-5 22 * * ?`
Every 5 minutes from 14:00 to 14:55 every day	`0 0/5 14 * * ?`	`0 0/5 22 * * ?`
Every 5 minutes from 14:00 to 14:55 and 18:00 to 18:55 every day	`0 0/5 14,18 * * ?`	`0 0/5 22,3 * * ?`
At 12:00 every Wednesday	`0 0 12 ? * WED`	`0 0 20 ? * WED`
At 10:15 on the 15th of every month	`0 15 10 15 * ?`	`0 15 18 15 * ?`
At 10:15 on the last day of every month	`0 15 10 L * ?`	`0 15 18 L * ?`
At 10:15 on the last Saturday of every month	`0 15 10 ? * 6L`	`0 15 18 ? * 6L`
At 10:15 on the third Saturday of every month	`0 15 10 ? * 6#3`	`0 15 18 ? * 6#3`
At 14:10 and 14:44 every Wednesday in March	`0 10,44 14 ? 3 WED`	`0 10,44 22 ? 3 WED`
At 10:15 every day in 2022	`0 15 10 ? * * 2022`	`0 15 18 ? * * 2022`
At 10:15 every day, every year	`0 15 10 ? * * *`	`0 15 18 ? * * *`
Every 5 minutes from 14:00 to 14:55 and 18:00 to 18:55 every day in 2022	`0 0/5 14,18 * * ? 2022`	`0 0/5 22,3 * * ? 2022`
At 10:15 on the third Saturday of every month in 2022 and 2023	`0 15 10 ? * 6#3 2022,2023`	`0 15 18 ? * 6#3 2022,2023`
Every 30 minutes from 09:00 to 17:30 every day from 2022 to 2025	`0 0/30 9-17 * * ? 2022-2025`	`0 0/30 17-2 * * ? 2022-2025`
At 14:10 and 14:44 every Wednesday in March, every two years starting from 2022	`0 10,44 14 ? 3 WED 2022/2`	`0 10,44 22 ? 3 WED 2022/2`