---
stage: Manage
group: Import
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers
---
# Export to CSV
This document lists the different implementations of CSV export in GitLab codebase.
| Export type | How it works | Advantages | Disadvantages | Existing examples |
|---|---|---|---|---|
| Streaming | - Query and yield data in batches to a response stream.
- Download starts immediately. | - Report available immediately. | - No progress indicator.
- Requires a reliable connection. | [Export Audit Event Log](../administration/audit_events.md#export-to-csv) |
| Downloading | - Query and write data in batches to a temporary file.
- Loads the file into memory.
- Sends the file to the client. | - Report available immediately. | - Large amount of data might cause request timeout.
- Memory intensive.
- Request expires when user navigates to a different page. | [Export Chain of Custody Report](../user/compliance/compliance_report/#chain-of-custody-report) |
| As email attachment | - Asynchronously process the query with background job.
- Email uses the export as an attachment. | - Asynchronous processing. | - Requires users use a different app (email) to download the CSV.
- Email providers may limit attachment size. | - [Export issues](../user/project/issues/csv_export.md)
- [Export merge requests](../user/project/merge_requests/csv_export.md) |
| As downloadable link in email (*) | - Asynchronously process the query with background job.
- Email uses an export link. | - Asynchronous processing.
- Bypasses email provider attachment size limit. | - Requires users use a different app (email).
- Requires additional storage and cleanup. | [Export User Permissions](https://gitlab.com/gitlab-org/gitlab/-/issues/1772) |
| Polling (non-persistent state) | - Asynchronously processes the query with the background job.
- Frontend(FE) polls every few seconds to check if CSV file is ready. | - Asynchronous processing.
- Automatically downloads to local machine on completion.
- In-app solution. | - Non-persistable request - request expires when user navigates to a different page.
- API is processed for each polling request. | [Export Vulnerabilities](../user/application_security/vulnerability_report/#export-vulnerability-details) |
| Polling (persistent state) (*) | - Asynchronously processes the query with background job.
- Backend (BE) maintains the export state
- FE polls every few seconds to check status.
- FE shows 'Download link' when export is ready.
- User can download or regenerate a new report. | - Asynchronous processing.
- No database calls made during the polling requests (HTTP 304 status is returned until export status changes).
- Does not require user to stay on page until export is complete.
- In-app solution.
- Can be expanded into a generic CSV feature (such as dashboard / CSV API). | - Requires to maintain export states in DB.
- Does not automatically download the CSV export to local machine, requires users to click 'Download' button. | [Export Merge Commits Report](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/43055) |
NOTE:
Export types marked as * are currently work in progress.