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+# Scheduled Tasks Pattern
+
+**Use Case**: Recurring automation workflows that run automatically on a schedule.
+
+---
+
+## Pattern Structure
+
+```
+Schedule Trigger → [Fetch Data] → [Process] → [Deliver] → [Log/Notify]
+```
+
+**Key Characteristic**: Time-based automated execution
+
+---
+
+## Core Components
+
+### 1. Schedule Trigger
+**Purpose**: Execute workflow at specified times
+
+**Modes**:
+- **Interval** - Every X minutes/hours/days
+- **Cron** - Specific times (advanced)
+- **Days & Hours** - Simple recurring schedule
+
+### 2. Data Source
+**Common sources**:
+- HTTP Request (APIs)
+- Database queries
+- File reads
+- Service-specific nodes
+
+### 3. Processing
+**Typical operations**:
+- Filter/transform data
+- Aggregate statistics
+- Generate reports
+- Check conditions
+
+### 4. Delivery
+**Output channels**:
+- Email
+- Slack/Discord/Teams
+- File storage
+- Database writes
+
+### 5. Logging
+**Purpose**: Track execution history
+
+**Methods**:
+- Database log entries
+- File append
+- Monitoring service
+
+---
+
+## Schedule Configuration
+
+### Interval Mode
+**Best for**: Simple recurring tasks
+
+**Examples**:
+```javascript
+// Every 15 minutes
+{
+  mode: "interval",
+  interval: 15,
+  unit: "minutes"
+}
+
+// Every 2 hours
+{
+  mode: "interval",
+  interval: 2,
+  unit: "hours"
+}
+
+// Every day at midnight
+{
+  mode: "interval",
+  interval: 1,
+  unit: "days"
+}
+```
+
+### Days & Hours Mode
+**Best for**: Specific days and times
+
+**Examples**:
+```javascript
+// Weekdays at 9 AM
+{
+  mode: "daysAndHours",
+  days: ["monday", "tuesday", "wednesday", "thursday", "friday"],
+  hour: 9,
+  minute: 0
+}
+
+// Every Monday at 6 PM
+{
+  mode: "daysAndHours",
+  days: ["monday"],
+  hour: 18,
+  minute: 0
+}
+```
+
+### Cron Mode (Advanced)
+**Best for**: Complex schedules
+
+**Examples**:
+```javascript
+// Every weekday at 9 AM
+{
+  mode: "cron",
+  expression: "0 9 * * 1-5"
+}
+
+// First day of every month at midnight
+{
+  mode: "cron",
+  expression: "0 0 1 * *"
+}
+
+// Every 15 minutes during business hours (9 AM - 5 PM) on weekdays
+{
+  mode: "cron",
+  expression: "*/15 9-17 * * 1-5"
+}
+```
+
+**Cron format**: `minute hour day month weekday`
+- `*` = any value
+- `*/15` = every 15 units
+- `1-5` = range (Monday-Friday)
+- `1,15` = specific values
+
+**Cron examples**:
+```
+0 */6 * * *      Every 6 hours
+0 9,17 * * *     At 9 AM and 5 PM daily
+0 0 * * 0        Every Sunday at midnight
+*/30 * * * *     Every 30 minutes
+0 0 1,15 * *     1st and 15th of each month
+```
+
+---
+
+## Common Use Cases
+
+### 1. Daily Reports
+**Flow**: Schedule → Fetch data → Aggregate → Format → Email
+
+**Example** (Sales report):
+```
+1. Schedule (daily at 9 AM)
+
+2. Postgres (query yesterday's sales)
+   SELECT date, SUM(amount) as total, COUNT(*) as orders
+   FROM orders
+   WHERE date = CURRENT_DATE - INTERVAL '1 day'
+   GROUP BY date
+
+3. Code (calculate metrics)
+   - Total revenue
+   - Order count
+   - Average order value
+   - Comparison to previous day
+
+4. Set (format email body)
+   Subject: Daily Sales Report - {{$json.date}}
+   Body: Formatted HTML with metrics
+
+5. Email (send to team@company.com)
+
+6. Slack (post summary to #sales)
+```
+
+### 2. Data Synchronization
+**Flow**: Schedule → Fetch from source → Transform → Write to target
+
+**Example** (CRM to data warehouse sync):
+```
+1. Schedule (every hour)
+
+2. Set (store last sync time)
+   SELECT MAX(synced_at) FROM sync_log
+
+3. HTTP Request (fetch new CRM contacts since last sync)
+   GET /api/contacts?updated_since={{$json.last_sync}}
+
+4. IF (check if new records exist)
+
+5. Set (transform CRM schema to warehouse schema)
+
+6. Postgres (warehouse - INSERT new contacts)
+
+7. Postgres (UPDATE sync_log SET synced_at = NOW())
+
+8. IF (error occurred)
+   └─ Slack (alert #data-team)
+```
+
+### 3. Monitoring & Health Checks
+**Flow**: Schedule → Check endpoints → Alert if down
+
+**Example** (Website uptime monitor):
+```
+1. Schedule (every 5 minutes)
+
+2. HTTP Request (GET https://example.com/health)
+   - timeout: 10 seconds
+   - continueOnFail: true
+
+3. IF (status !== 200 OR response_time > 2000ms)
+
+4. Redis (check alert cooldown - don't spam)
+   - Key: alert:website_down
+   - TTL: 30 minutes
+
+5. IF (no recent alert sent)
+
+6. [Alert Actions]
+   ├─ Slack (notify #ops-team)
+   ├─ PagerDuty (create incident)
+   ├─ Email (alert@company.com)
+   └─ Redis (set alert cooldown)
+
+7. Postgres (log uptime check result)
+```
+
+### 4. Cleanup & Maintenance
+**Flow**: Schedule → Find old data → Archive/Delete → Report
+
+**Example** (Database cleanup):
+```
+1. Schedule (weekly on Sunday at 2 AM)
+
+2. Postgres (find old records)
+   SELECT * FROM logs
+   WHERE created_at < NOW() - INTERVAL '90 days'
+   LIMIT 10000
+
+3. IF (records exist)
+
+4. Code (export to JSON for archive)
+
+5. Google Drive (upload archive file)
+   - Filename: logs_archive_{{$now.format('YYYY-MM-DD')}}.json
+
+6. Postgres (DELETE archived records)
+   DELETE FROM logs
+   WHERE id IN ({{$json.archived_ids}})
+
+7. Slack (report: "Archived X records, deleted Y records")
+```
+
+### 5. Data Enrichment
+**Flow**: Schedule → Find incomplete records → Enrich → Update
+
+**Example** (Enrich contacts with company data):
+```
+1. Schedule (nightly at 3 AM)
+
+2. Postgres (find contacts without company data)
+   SELECT id, email, domain FROM contacts
+   WHERE company_name IS NULL
+   AND created_at > NOW() - INTERVAL '7 days'
+   LIMIT 100
+
+3. Split In Batches (10 contacts per batch)
+
+4. HTTP Request (call Clearbit enrichment API)
+   - For each contact domain
+   - Rate limit: wait 1 second between batches
+
+5. Set (map API response to database schema)
+
+6. Postgres (UPDATE contacts with company data)
+
+7. Wait (1 second - rate limiting)
+
+8. Loop (back to step 4 until all batches processed)
+
+9. Email (summary: "Enriched X contacts")
+```
+
+### 6. Backup Automation
+**Flow**: Schedule → Export data → Compress → Store → Verify
+
+**Example** (Database backup):
+```
+1. Schedule (daily at 2 AM)
+
+2. Code (execute pg_dump)
+   const { exec } = require('child_process');
+   exec('pg_dump -h db.example.com mydb > backup.sql')
+
+3. Code (compress backup)
+   const zlib = require('zlib');
+   // Compress backup.sql to backup.sql.gz
+
+4. AWS S3 (upload compressed backup)
+   - Bucket: backups
+   - Key: db/backup-{{$now.format('YYYY-MM-DD')}}.sql.gz
+
+5. AWS S3 (list old backups)
+   - Keep last 30 days only
+
+6. AWS S3 (delete old backups)
+
+7. IF (error occurred)
+   ├─ PagerDuty (critical alert)
+   └─ Email (backup failed!)
+   ELSE
+   └─ Slack (#devops: "✅ Backup completed")
+```
+
+### 7. Content Publishing
+**Flow**: Schedule → Fetch content → Format → Publish
+
+**Example** (Automated social media posts):
+```
+1. Schedule (every 3 hours during business hours)
+   - Cron: 0 9,12,15,18 * * 1-5
+
+2. Google Sheets (read content queue)
+   - Sheet: "Scheduled Posts"
+   - Filter: status=pending AND publish_time <= NOW()
+
+3. IF (posts available)
+
+4. HTTP Request (shorten URLs in post)
+
+5. HTTP Request (POST to Twitter API)
+
+6. HTTP Request (POST to LinkedIn API)
+
+7. Google Sheets (update status=published)
+
+8. Slack (notify #marketing: "Posted: {{$json.title}}")
+```
+
+---
+
+## Timezone Considerations
+
+### Set Workflow Timezone
+```javascript
+// In workflow settings
+{
+  timezone: "America/New_York"  // EST/EDT
+}
+```
+
+### Common Timezones
+```
+America/New_York    - Eastern (US)
+America/Chicago     - Central (US)
+America/Denver      - Mountain (US)
+America/Los_Angeles - Pacific (US)
+Europe/London       - GMT/BST
+Europe/Paris        - CET/CEST
+Asia/Tokyo          - JST
+Australia/Sydney    - AEDT
+UTC                 - Universal Time
+```
+
+### Handle Daylight Saving
+**Best practice**: Use timezone-aware scheduling
+
+```javascript
+// ❌ Bad: UTC schedule for "9 AM local"
+// Will be off by 1 hour during DST transitions
+
+// ✅ Good: Set workflow timezone
+{
+  timezone: "America/New_York",
+  schedule: {
+    mode: "daysAndHours",
+    hour: 9  // Always 9 AM Eastern, regardless of DST
+  }
+}
+```
+
+---
+
+## Error Handling
+
+### Pattern 1: Error Trigger Workflow
+**Main workflow**: Normal execution
+**Error workflow**: Alerts and recovery
+
+**Main**:
+```
+Schedule → Fetch → Process → Deliver
+```
+
+**Error**:
+```
+Error Trigger (for main workflow)
+  → Set (extract error details)
+  → Slack (#ops-team: "❌ Scheduled job failed")
+  → Email (admin alert)
+  → Postgres (log error for analysis)
+```
+
+### Pattern 2: Retry with Backoff
+```
+Schedule → HTTP Request (continueOnFail: true)
+  → IF (error)
+    ├─ Wait (5 minutes)
+    ├─ HTTP Request (retry 1)
+    └─ IF (still error)
+      ├─ Wait (15 minutes)
+      ├─ HTTP Request (retry 2)
+      └─ IF (still error)
+        └─ Alert admin
+```
+
+### Pattern 3: Partial Failure Handling
+```
+Schedule → Split In Batches
+  → Process (continueOnFail: true)
+  → Code (track successes and failures)
+  → Report:
+    "✅ Processed: 95/100"
+    "❌ Failed: 5/100"
+```
+
+---
+
+## Performance Optimization
+
+### 1. Batch Processing
+For large datasets:
+
+```
+Schedule → Query (LIMIT 10000)
+  → Split In Batches (100 items)
+  → Process batch
+  → Loop
+```
+
+### 2. Parallel Processing
+When operations are independent:
+
+```
+Schedule
+  ├─ [Branch 1: Update DB]
+  ├─ [Branch 2: Send emails]
+  └─ [Branch 3: Generate report]
+  → Merge (wait for all) → Final notification
+```
+
+### 3. Skip if Already Running
+Prevent overlapping executions:
+
+```
+Schedule → Redis (check lock)
+  → IF (lock exists)
+    └─ End (skip this execution)
+  → ELSE
+    ├─ Redis (set lock, TTL 30 min)
+    ├─ [Execute workflow]
+    └─ Redis (delete lock)
+```
+
+### 4. Early Exit on No Data
+Don't waste time if nothing to process:
+
+```
+Schedule → Query (check if work exists)
+  → IF (no results)
+    └─ End workflow (exit early)
+  → ELSE
+    └─ Process data
+```
+
+---
+
+## Monitoring & Logging
+
+### Pattern 1: Execution Log Table
+```sql
+CREATE TABLE workflow_executions (
+  id SERIAL PRIMARY KEY,
+  workflow_name VARCHAR(255),
+  started_at TIMESTAMP,
+  completed_at TIMESTAMP,
+  status VARCHAR(50),
+  records_processed INT,
+  error_message TEXT
+);
+```
+
+**Log execution**:
+```
+Schedule
+  → Set (record start)
+  → [Workflow logic]
+  → Postgres (INSERT execution log)
+```
+
+### Pattern 2: Metrics Collection
+```
+Schedule → [Execute]
+  → Code (calculate metrics)
+    - Duration
+    - Records processed
+    - Success rate
+  → HTTP Request (send to monitoring system)
+    - Datadog, Prometheus, etc.
+```
+
+### Pattern 3: Summary Notifications
+Daily/weekly execution summaries:
+
+```
+Schedule (daily at 6 PM) → Query execution logs
+  → Code (aggregate today's executions)
+  → Email (summary report)
+    "Today's Workflow Executions:
+     - 24/24 successful
+     - 0 failures
+     - Avg duration: 2.3 min"
+```
+
+---
+
+## Testing Scheduled Workflows
+
+### 1. Use Manual Trigger for Testing
+**Development pattern**:
+```
+Manual Trigger (for testing)
+  → [Same workflow logic]
+  → [Outputs]
+
+// Once tested, replace with Schedule Trigger
+```
+
+### 2. Test with Different Times
+```javascript
+// Code node - simulate different times
+const testTime = new Date('2024-01-15T09:00:00Z');
+return [{ json: { currentTime: testTime } }];
+```
+
+### 3. Dry Run Mode
+```
+Schedule → Set (dryRun: true)
+  → IF (dryRun)
+    └─ Log what would happen (don't execute)
+  → ELSE
+    └─ Execute normally
+```
+
+### 4. Shorter Interval for Testing
+```javascript
+// Testing: every 1 minute
+{
+  mode: "interval",
+  interval: 1,
+  unit: "minutes"
+}
+
+// Production: every 1 hour
+{
+  mode: "interval",
+  interval: 1,
+  unit: "hours"
+}
+```
+
+---
+
+## Common Gotchas
+
+### 1. ❌ Wrong: Ignoring timezone
+```javascript
+Schedule (9 AM)  // 9 AM in which timezone?
+```
+
+### ✅ Correct: Set workflow timezone
+```javascript
+// Workflow settings
+{
+  timezone: "America/New_York"
+}
+```
+
+### 2. ❌ Wrong: Overlapping executions
+```
+Schedule (every 5 min) → Long-running task (10 min)
+// Two executions running simultaneously!
+```
+
+### ✅ Correct: Add execution lock
+```
+Schedule → Redis (check lock)
+  → IF (locked) → Skip
+  → ELSE → Execute
+```
+
+### 3. ❌ Wrong: No error handling
+```
+Schedule → API call → Process (fails silently)
+```
+
+### ✅ Correct: Add error workflow
+```
+Main: Schedule → Execute
+Error: Error Trigger → Alert
+```
+
+### 4. ❌ Wrong: Processing all data at once
+```
+Schedule → SELECT 1000000 records → Process (OOM)
+```
+
+### ✅ Correct: Batch processing
+```
+Schedule → SELECT with pagination → Split In Batches → Process
+```
+
+### 5. ❌ Wrong: Hardcoded dates
+```javascript
+query: "SELECT * FROM orders WHERE date = '2024-01-15'"
+```
+
+### ✅ Correct: Dynamic dates
+```javascript
+query: "SELECT * FROM orders WHERE date = CURRENT_DATE - INTERVAL '1 day'"
+```
+
+---
+
+## Real Template Examples
+
+From n8n template library:
+
+**Template #2947** (Weather to Slack):
+```
+Schedule (daily 8 AM)
+  → HTTP Request (weather API)
+  → Set (format message)
+  → Slack (post to #general)
+```
+
+**Daily backup**:
+```
+Schedule (nightly 2 AM)
+  → Postgres (export data)
+  → Google Drive (upload)
+  → Email (confirmation)
+```
+
+**Monitoring**:
+```
+Schedule (every 5 min)
+  → HTTP Request (health check)
+  → IF (down) → PagerDuty alert
+```
+
+Use `search_templates({query: "schedule"})` to find more!
+
+---
+
+## Checklist for Scheduled Workflows
+
+### Planning
+- [ ] Define schedule frequency (interval, cron, days & hours)
+- [ ] Set workflow timezone
+- [ ] Estimate execution duration
+- [ ] Plan for failures and retries
+- [ ] Consider timezone and DST
+
+### Implementation
+- [ ] Configure Schedule Trigger
+- [ ] Set workflow timezone in settings
+- [ ] Add early exit for no-op cases
+- [ ] Implement batch processing for large data
+- [ ] Add execution logging
+
+### Error Handling
+- [ ] Create Error Trigger workflow
+- [ ] Implement retry logic
+- [ ] Add alert notifications
+- [ ] Log errors for analysis
+- [ ] Handle partial failures gracefully
+
+### Monitoring
+- [ ] Log each execution (start, end, status)
+- [ ] Track metrics (duration, records, success rate)
+- [ ] Set up daily/weekly summaries
+- [ ] Alert on consecutive failures
+- [ ] Monitor resource usage
+
+### Testing
+- [ ] Test with Manual Trigger first
+- [ ] Verify timezone behavior
+- [ ] Test error scenarios
+- [ ] Check for overlapping executions
+- [ ] Validate output quality
+
+### Deployment
+- [ ] Document workflow purpose
+- [ ] Set up monitoring
+- [ ] Configure alerts
+- [ ] Activate workflow in n8n UI ⚠️ **Manual activation required** (API/MCP cannot activate)
+- [ ] Test in production (short interval first)
+- [ ] Monitor first few executions
+
+---
+
+## Advanced Patterns
+
+### Dynamic Scheduling
+**Change schedule based on conditions**:
+
+```
+Schedule (check every hour) → Code (check if it's time to run)
+  → IF (business hours AND weekday)
+    └─ Execute workflow
+  → ELSE
+    └─ Skip
+```
+
+### Dependent Schedules
+**Chain workflows**:
+
+```
+Workflow A (daily 2 AM): Data sync
+  → On completion → Trigger Workflow B
+
+Workflow B: Generate report (depends on fresh data)
+```
+
+### Conditional Execution
+**Skip based on external factors**:
+
+```
+Schedule → HTTP Request (check feature flag)
+  → IF (feature enabled)
+    └─ Execute
+  → ELSE
+    └─ Skip
+```
+
+---
+
+## Summary
+
+**Key Points**:
+1. **Set workflow timezone** explicitly
+2. **Batch processing** for large datasets
+3. **Error handling** is critical (Error Trigger + retries)
+4. **Prevent overlaps** with execution locks
+5. **Monitor and log** all executions
+
+**Pattern**: Schedule → Fetch → Process → Deliver → Log
+
+**Schedule Modes**:
+- **Interval**: Simple recurring (every X minutes/hours)
+- **Days & Hours**: Specific days and times
+- **Cron**: Advanced complex schedules
+
+**Related**:
+- [http_api_integration.md](http_api_integration.md) - Fetching data on schedule
+- [database_operations.md](database_operations.md) - Scheduled database tasks
+- [webhook_processing.md](webhook_processing.md) - Alternative to scheduling