Data Refresh
Keep your analysis current with automatic and on-demand data updates.
What is Data Refresh?
Data refresh is how Shadowfax updates Sources with the latest data from file uploads. When data refreshes, all dependent Views recalculate automatically thanks to the reactive system, ensuring your entire analysis stays current. Database refresh capabilities are coming soon.
Fresh data flows through your entire pipeline automatically
Why Data Refresh Matters
Always current: Dashboards reflect the latest data without manual updates.
Automatic propagation: Refresh one Source, all downstream Views update.
Scheduled updates: Set it once, forget about it—data refreshes on schedule.
Time savings: No manual CSV exports and re-uploads.
Trust: Confidence that your analysis is based on current data.
How Data Refresh Works
The Refresh Process
- Trigger: Manual click, scheduled time, or file re-upload
- Fetch: Shadowfax queries the database or processes the file
- Update Source: New data replaces old in the Source
- Propagate: Reactive system detects change
- Recalculate: All dependent Views update automatically
- Refresh visualizations: Charts and dashboards show new data
Typically completes in seconds to minutes, depending on data volume.
Step-by-step refresh and propagation
Refresh Options
Manual Refresh
What it is: You trigger refresh whenever you want fresh data.
How to do it:
- Right-click the Source node
- Select "Refresh data"
- Wait for refresh to complete
- Views update automatically
Best for:
- Ad-hoc analysis
- Infrequently changing data
- Cost-sensitive database queries
- Testing before scheduling
Indicators: Loading spinner while refreshing, timestamp updates when complete
Right-click menu with Refresh option
Scheduled Refresh
What it is: Automatic refresh at regular intervals.
Options:
- Hourly: Every hour at the top of the hour
- Daily: Once per day (usually early morning)
- Custom: Specific times or intervals (if supported)
How to configure:
- Go to Source settings
- Select "Refresh schedule"
- Choose frequency (hourly, daily)
- Set time (for daily)
- Save
Best for:
- Operational dashboards
- Regular reporting
- Monitoring live systems
Refresh schedule settings
File Re-Upload Refresh
What it is: Upload a new version of a file to replace the old one.
How to do it:
- Click the Source you want to update
- Select "Replace file"
- Upload new file (same schema expected)
- Shadowfax validates and updates
- Views recalculate
Best for:
- CSV or Excel Sources
- Weekly or monthly data drops
- Replacing snapshots
Important: New file should have the same columns—Views depend on schema consistency.
Refresh Frequency Considerations
Hourly Refresh
Pros:
- Near-real-time dashboards
- Catch operational issues quickly
- Up-to-date for fast-moving data
Cons:
- More database load
- Higher query costs (for billed databases)
- May not be necessary for slow-changing data
Good for: Operations dashboards, live monitoring, SaaS metrics
Daily Refresh
Pros:
- Fresh data for daily reports
- Lower database load
- Cost-effective
- Sufficient for most business analysis
Cons:
- Not real-time
- Delayed insights for fast-moving data
Good for: Daily reports, trend analysis, executive dashboards
Manual (On-Demand) Refresh
Pros:
- Full control over timing
- No unnecessary queries
- Cost-effective for exploration
Cons:
- Requires remembering to refresh
- Risk of analyzing stale data
- Not suitable for shared dashboards
Good for: Ad-hoc analysis, one-time investigations, development/testing
Refresh frequency trade-offs
Understanding Refresh Status
Status Indicators
Last refreshed: Timestamp showing when data was last updated Refreshing: Loading spinner during active refresh Failed: Error icon if refresh encountered issues Scheduled next: Shows when next auto-refresh will occur
Viewing Refresh History
Some setups show refresh history:
- Timestamps of past refreshes
- Success/failure status
- Error messages (if failed)
Use this to troubleshoot issues or verify refresh patterns.
Refresh history log showing past updates
Automatic View Recalculation
The Reactive Chain
When a Source refreshes:
Source updates
↓
First-level Views recalculate (directly use Source)
↓
Second-level Views recalculate (use first-level Views)
↓
...continue downstream...
↓
Visualizations refresh
All automatic, all consistent.
Performance Impact
Small data: Views recalculate in seconds Large data: May take minutes for complex pipelines Progress indicators: See which Views are updating
The system processes updates in dependency order for consistency.
Handling Schema Changes
Same Schema (Safe)
If new data has the same columns:
- Refresh works smoothly
- Views continue working
- No issues
Schema Changes (Risky)
If columns are added, removed, or renamed:
- Views referencing missing columns may break
- Error messages appear
- Manual fixes needed
Best practice: Keep schema stable. If schema must change, update Views to match.
Notification of Issues
If a refresh causes downstream errors:
- Red error indicators on broken Views
- Error messages explaining what broke
- You can fix Views and re-run
Warning when schema change breaks Views
Refreshing Multiple Sources
Independent Sources
If you have multiple database connections:
- Each refreshes on its own schedule
- Timing may differ
- Views update as each Source refreshes
Coordinating Refreshes
Challenge: Source A refreshes at 8am, Source B at 9am—Views using both may be inconsistent for an hour.
Solution:
- Align refresh schedules (both at 8am)
- Or use manual refresh to sync timing
Dependency Awareness
Views joining multiple Sources:
- Recalculate whenever any input Source refreshes
- Always show data consistent with current Source states
Cost and Performance Considerations
Network and Storage
Large datasets:
- Longer transfer times
- More storage in Shadowfax
- Consider filtering data before upload when possible
Managing data efficiently
Troubleshooting Refresh Issues
Refresh Failed
Common causes:
- Database connection lost
- Database credentials changed
- Query timeout (data too large)
- Schema changed
- Network issues
Solutions:
- Check connection settings
- Verify credentials still valid
- Test database connectivity
- Review error messages
- Contact database admin if needed
Views Not Updating
Cause: Refresh succeeded but Views didn't recalculate
Solutions:
- Check View dependencies (should be automatic)
- Refresh page
- Manually trigger View recalculation (if option available)
Slow Refresh
Causes:
- Large dataset
- Slow database query
- Complex downstream Views
Solutions:
- Optimize database queries (indexes, views)
- Reduce data volume (filter, sample)
- Simplify View logic
Best Practices
Match refresh to data change frequency: If data updates daily, daily refresh is sufficient.
Align schedules: For joined Sources, sync refresh times.
Monitor costs: Track database query costs and adjust frequency if needed.
Test before scheduling: Use manual refresh to verify everything works.
Notify stakeholders: Let dashboard users know when data refreshes (e.g., "Daily at 6am EST").
Handle failures gracefully: Set up alerts if refresh fails (if supported).
Document refresh schedules: Keep a record of what refreshes when.
Use off-peak times: Schedule database queries during low-traffic periods.
Archive old snapshots: If analyzing historical states, export old data before refresh overwrites it.
Refresh and Collaboration
When working with a team:
- All users see refreshed data: Shared Sources update for everyone
- No version conflicts: Everyone always on the latest data
- Coordinated schedules: Team agrees on refresh timing
Related Features
- Sources - What gets refreshed
- Reactive System - How changes propagate
- Views - What recalculates after refresh