> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://notion.ferndocs.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://notion.ferndocs.com/_mcp/server.

# Multi-Source Databases: API Version 2025-09-03 Announcement

#### 📣 Important API update coming September 3rd

We're introducing multi-source databases to Notion! Our new API version `2025-09-03` separates "**databases**" (containers) from "**data sources**" (tables), unlocking powerful new organizational capabilities.

#### What you need to know

- Current integrations continue working with single-source databases
- Update to the new API version to support multi-source databases
- We're introducing the concept of API versioning to [integration webhooks](/reference/webhooks) as well

Start upgrading your integrations now to ensure a smooth transition when users begin creating additional data sources starting from September 3rd.

**Full details and migration guide**: [Upgrading to 2025-09-03](/docs/upgrade-guide-2025-09-03)

**General information about API versioning**: [Versioning](/reference/versioning)