Supabase Storage¶

OpenSheets supports optional cloud storage via Supabase, a hosted PostgreSQL backend. When configured, spreadsheet data is saved to a Supabase table and can be loaded from any device.

Opening Settings¶

Open via File > Storage Settings in the menu bar. The settings dialog lets you configure, test, and manage your Supabase connection.

Setup¶

1. Create a Supabase Table¶

In your Supabase project, create a table with this schema:

CREATE TABLE spreadsheets (
  id TEXT PRIMARY KEY,
  data JSONB,
  updated_at TIMESTAMPTZ
);

Enable Row Level Security (RLS) policies as needed for your use case.

2. Configure Connection¶

In the settings dialog, enter:

Field	Description
Supabase URL	Your project URL, e.g. `https://xxxxx.supabase.co`
Anon / Public Key	The `anon` key from your Supabase project settings
Table Name	The table name (default: `spreadsheets`)

Click Test Connection to verify the settings, then Save Settings to persist them to localStorage.

Features¶

Auto-Save¶

When enabled (on by default), OpenSheets checks for unsaved changes every 30 seconds and automatically saves to Supabase. The auto-save toggle is available in the settings dialog.

Changes are tracked by listening to cell edits, undo/redo, sheet operations, and other modification events.

Sync Status Indicator¶

A colored dot appears next to the save button in the toolbar:

Color	State	Meaning
Green	Synced	All changes are saved
Orange	Unsaved	Local changes not yet saved
Spinning	Saving	Save in progress
Red	Error	Last save failed
Gray	Offline	Not connected to Supabase

Conflict Detection¶

Before saving, OpenSheets checks the server's updated_at timestamp. If the document was modified externally since your last save, a prompt offers two choices:

Overwrite: Save your version, replacing the server copy.
Load server version: Discard your local changes and load the latest from Supabase.

Document Management¶

The settings dialog includes a document list showing all saved spreadsheets with:

Document title and ID
Last updated timestamp
File size in KB

Each document supports these actions:

Load: Open the document in the current session.
Rename: Change the document title.
Duplicate: Create a copy with a new ID.
Delete: Permanently remove from Supabase.

Use the search bar and sort buttons (Name, Date, Size) to find documents quickly.

Import / Export Backups¶

Download Backup: Save the complete workbook as a local JSON file.
Upload Backup: Restore a workbook from a previously downloaded JSON file.

Connection Health Monitoring¶

A health check runs every 60 seconds in the background. The connection status is displayed in the settings dialog and reflected in the sync indicator.

What Is Stored in Supabase¶

Only cell and sheet data is stored in Supabase:

Sheet names, cell values, formulas, and formatting
Data validation rules, conditional formatting
Sheet protection settings

Configuration items (saved queries, forms, custom scripts, chart positions) are stored in the URL hash, not in Supabase. This separation keeps the database payload focused on data while portable configuration travels with the link.

Disabling Supabase¶

Click Disable / Clear in the settings dialog to remove all connection settings. Data will be saved exclusively to the URL hash and browser localStorage.