Historical Data Export
Historical export generates files in the background for retaining raw records or analysis in other tools, without requiring the browser to wait for queries to finish.
Export steps
Section titled “Export steps”- Select points and a time range; specify the source device for shared points.
- Review the disk-space estimate, then create an export task.
- Track queued, running, completed, or failed status in the task list; cancel tasks that are no longer needed.
- After completion, obtain a short-lived download ticket and download the CSV or ZIP file.
Tasks are limited by time span, file size, concurrency, and available disk space. Insufficient space causes exports to be rejected or stopped. Actual limits depend on device configuration.
Files and data
Section titled “Files and data”- Supports acquisition, aggregation, and shared historical values. Do not select the same point from the same device more than once.
- CSV preserves null markers to distinguish missing data from empty strings.
- Download tickets expire; obtain a new one after expiration. Do not share tickets publicly.
- Exports include data still retained within the specified range. History deleted by retention policies cannot be recovered.
Integration APIs
Section titled “Integration APIs”| Operation | API |
|---|---|
| Capacity estimate | GET /ems-data/export/disk-space |
| Create task / query task list | POST /ems-data/export/tasks / GET /ems-data/export/tasks |
| Query / cancel a task | GET /ems-data/export/tasks/:taskId / DELETE /ems-data/export/tasks/:taskId |
| Obtain download ticket | POST /ems-data/export/tasks/:taskId/download-ticket |
Creating a task requires format (CSV or CSV_ZIP), dataKeys, startTime, and endTime. Downloads are available only after task success. Acceptance does not mean the file has been generated.
Use Historical queries for ad hoc analysis, Periodic archiving for ongoing retention, and Backup and restore for configuration migration. For Agent invocation, see the export Skill.