When an HRIS Link component is initially enabled, your Greenhouse consultant triggers a one-time import, which updates Greenhouse Recruiting records and ensures data is in sync with the corresponding HRIS records. After this initial run, your Greenhouse consultant enables polling (every 15 minutes), and all subsequent HRIS Link updates are based on change detection.
With HRIS Link polling enabled, data is updated in Greenhouse Recruiting only if there is an update to the data in the HRIS report. This means if someone in your organization makes an update to a job, department, office, or user in Greenhouse Recruiting, that update won’t necessarily be overwritten the next time HRIS Link runs; rather, it will only be overwritten in Greenhouse Recruiting the next time an update is made to that job, department, office, or user in your HRIS.
On the backend, HRIS link compares the most recent version of an HRIS report to the previous version to determine which (if any) records have been updated since the last run of HRIS Link. If HRIS Link finds a record has been updated in your HRIS, the integration will update the corresponding record in Greenhouse to match the data included in the latest HRIS report.
To prevent data from falling out of sync between your HRIS and Greenhouse Recruiting, we recommend leveraging the API Only setting on job custom fields where your HRIS should be the source of truth. This locks down the field and prevents users from making manual updates in Greenhouse Recruiting. To learn more, please see the following article: Harvest-only custom job fields