# 11. Reference

*Tabellum for mobile, chapter 11. On the web: https://tabellum.dudko.dev/manual/mobile/reference*

## 11.1 Databases

| **Database** | **Notes** |
| --- | --- |
| PostgreSQL | Everything in this guide, including enum types, extensions, materialized views and plans |
| MySQL, MariaDB | Schemas are databases; users and roles with the server’s own flags |
| SQL Server | Schemas, procedures, table-valued functions, users and roles |
| BigQuery | A dry run tells how many bytes a statement would process before it runs; access is managed in Google Cloud |
| SQLite | A file in the workspace; nothing to install |
| MongoDB | Collections as tables; find and aggregate pipelines in the editor |

## 11.2 This guide in Tabellum

The same guide is inside the app, screenshots and marks included, and needs no network: tap **User guide** in the command palette (the search button in the title bar), or the **User guide** button in Help (the **?** at the bottom of the menu). The chapter list switches to the desktop guide. On the website it is at tabellum.dudko.dev/manual, a page per chapter, with this PDF.

## 11.3 On a phone

The phone app is the same Tabellum as on a computer, with these differences:

- The workspace is inside the app, not a folder you choose.
- Backups go through the database connection, not tools such as `pg_dump`.
- There is no SSH agent; paste private keys into the tunnel instead.
- Sync goes through the GitHub, GitLab or Bitbucket API.
- There is no MCP server for external AI tools.
- Updates come from the App Store or Google Play.

The engine that talks to the databases runs inside the app. **Engine** in the command palette can point the app at a Tabellum worker you host instead, for databases only that machine can reach.

## 11.4 If something goes wrong

- **A connection fails.** The message under it says what failed and what to check. “Connection refused” means nothing listens on that host and port; a timeout usually means a firewall or a VPN — or a server that only your office network can reach.
- **A query takes too long.** Tap the red **Stop** button.
- **The agent does not answer.** Check its API key and model in the agent’s settings; **What was sent** in the agent’s page shows each request.
- **A design wants to undo someone else’s change.** Use **Reload from the database** (see [Section 7](https://tabellum.dudko.dev/manual/mobile/the-schema-designer)).

Support: tabellum.dudko.dev/support.