# Schedule expression reference


Use these reference tables to construct schedule expressions for your scheduled queries. All times are in UTC.

**Cron expression syntax**

Format: `cron(minute hour day-of-month month day-of-week year)`


| Use Case | Cron Expression | Description | Use When | 
| --- | --- | --- | --- | 
| Daily Schedules | cron(0 9 \$1 \$1 ? \$1) | Every day at 9:00 AM UTC | Daily reports | 
|  | cron(0 \$1/6 \$1 \$1 ? \$1) | Every 6 hours (00:00, 06:00, 12:00, 18:00 UTC) | Frequent monitoring | 
|  | cron(30 2 \$1 \$1 ? \$1) | Every day at 2:30 AM UTC | Off-peak analysis | 
| Business Hours | cron(0 9-17 ? \$1 MON-FRI \$1) | Every hour from 9 AM to 5 PM, Monday to Friday UTC | Business monitoring | 
|  | cron(0 18 ? \$1 MON-FRI \$1) | Weekdays at 6:00 PM UTC | End of business day | 
|  | cron(0 8,12,17 ? \$1 MON-FRI \$1) | 8 AM, noon, and 5 PM on weekdays UTC | Key business times | 
| Weekly Schedules | cron(0 12 ? \$1 SUN \$1) | Every Sunday at noon UTC | Weekly summaries | 
|  | cron(0 9 ? \$1 MON \$1) | Every Monday at 9:00 AM UTC | Week start reports | 
|  | cron(0 23 ? \$1 FRI \$1) | Every Friday at 11:00 PM UTC | Week end cleanup | 
| Monthly Schedules | cron(0 0 1 \$1 ? \$1) | First day of every month at midnight UTC | Monthly reports | 
|  | cron(0 9 L \$1 ? \$1) | Last day of every month at 9:00 AM UTC | Month end processing | 
|  | cron(0 10 1 1,4,7,10 ? \$1) | First day of each quarter at 10:00 AM UTC | Quarterly analysis | 
| High Frequency | cron(\$1/15 \$1 \$1 \$1 ? \$1) | Every 15 minutes | Real-time monitoring | 
|  | cron(0,30 \$1 \$1 \$1 ? \$1) | Every 30 minutes (at :00 and :30) | Frequent checks | 
|  | cron(0 \$1/2 \$1 \$1 ? \$1) | Every 2 hours | Regular intervals | 
| Special Cases | cron(30 8 1 1 ? \$1) | January 1st at 8:30 AM UTC | Annual reports | 
|  | cron(0 6 \$1 \$1 SAT,SUN \$1) | Weekends at 6:00 AM UTC | Weekend processing | 
|  | cron(0 0 ? \$1 MON\$11 \$1) | First Monday of every month at midnight UTC | Monthly planning | 

**Cron expression field reference**


| Field | Values | Wildcards | Examples | 
| --- | --- | --- | --- | 
| Minute (1st) | 0-59 | \$1 , - / | 0 (top of hour), \$1/15 (every 15 min), 0,30 (twice hourly) | 
| Hour (2nd) | 0-23 | \$1 , - / | 9 (9 AM), \$1/2 (every 2 hrs), 9-17 (business hours) | 
| Day-of-month (3rd) | 1-31, L, W | \$1 , - / ? | 1 (1st day), L (last day), ? (when using day-of-week) | 
| Month (4th) | 1-12 or JAN-DEC | \$1 , - / | 1 (January), JAN, 1,4,7,10 (quarterly) | 
| Day-of-week (5th) | 1-7 or SUN-SAT | \$1 , - / ? \$1 L | MON-FRI (weekdays), SUN, MON\$11 (1st Monday) | 
| Year (6th) | 1970-2199 | \$1 , - / | \$1 (every year), 2024 (specific year), 2024-2026 (range) | 

**Wildcard characters and special expressions**

**`*` (asterisk)**  
Matches all values in the field. Example: `*` in the hour field means every hour.

**`?` (question mark)**  
No specific value. Use in day-of-month or day-of-week when the other is specified. Example: Use `?` in day-of-month when specifying `MON-FRI` in day-of-week.

**`-` (dash)**  
Range of values. Example: `MON-FRI` (Monday through Friday), `9-17` (9 AM through 5 PM).

**`,` (comma)**  
Multiple specific values. Example: `MON,WED,FRI` (Monday, Wednesday, Friday), `8,12,17` (8 AM, noon, 5 PM).

**`/` (slash)**  
Step values or increments. Example: `0/15` in minutes means every 15 minutes starting at minute 0 (0, 15, 30, 45). `*/2` in hours means every 2 hours.

**`L` (last)**  
Last day of month or last occurrence of weekday. Example: `L` in day-of-month means last day of month. `FRIL` means last Friday of month.

**`W` (weekday)**  
Nearest weekday. Example: `15W` means nearest weekday to the 15th of the month.

**`#` (nth occurrence)**  
Nth occurrence of weekday in month. Example: `MON#1` means first Monday of month, `FRI#2` means second Friday of month.

**Common patterns and best practices**
+ **For business applications:** Use `MON-FRI` and business hours (e.g., `9-17`) to avoid running queries during weekends or off-hours.
+ **For high-frequency monitoring:** Use increments like `*/15` (every 15 minutes) but be mindful of query concurrency limits.
+ **For resource efficiency:** Schedule resource-intensive queries during off-peak hours using early morning times like `2-6` UTC.
+ **For monthly reports:** Use `L` for last day of month or specific dates like `1` for first day to ensure consistent timing.