Understanding the Database
FundOS stores everything — accounts, funds, transactions, budgets — in a single local file called the database. There is no server and no account. The file lives on your machine and nowhere else.
When FundOS starts and finds no existing database, it creates a fresh one automatically and opens to the locale setup screen. You will see that screen next.
The Database Menu
The database icon in the bottom-right corner of the window opens the database menu.
The top section shows information about the current database. Size on disk is useful to know before backing up. Schema version identifies the structure of your database — if you ever need to report an issue on GitHub, include this number.
The Actions section has four options.
Manage Locale… reopens the locale setup screen so you can adjust your currency or percentage formatting. See Choosing a Locale for details.
Back Up Database… saves a copy of the database file to a location you choose. Backups are plain copies — you can restore one at any time by choosing Restore from Backup. Back up before making large changes and before any software update.
Restore from Backup… replaces the current database with a backup you select. FundOS will warn you and recommend backing up before proceeding, since the current database will be discarded.
Replace with New Database… discards the current database and creates a fresh one. FundOS will warn you and recommend backing up before proceeding. Use this if you want to start over or maintain a separate database for a different purpose.
If Something Goes Wrong
FundOS validates the database when it opens. Most users will never see an error here, but if you do, the error screen will tell you what happened and offer recovery options. Back up before attempting any recovery.
| Error | What it means | What to do |
|---|---|---|
| Database Requires a Newer Version | This database was created by a newer version of FundOS. | Update FundOS, or restore an older backup. |
| Unrecognized Database File | The database file was not created by FundOS and cannot be read. | Restore from a backup, or create a new database. |
| Database Schema is Corrupted | The database structure is unrecognized and cannot be recovered. | Restore from a backup, or create a new database. |
| Database is Corrupted | The database file is damaged and cannot be opened. | Restore from a backup, or create a new database. |
| Database Unavailable | The database is busy or locked by another process. | Restart FundOS. If the problem persists, restart your computer. |
| Can’t Open Database | The path to the database does not exist or FundOS does not have permission to access it. | Check that the database file exists at its expected location (Windows: C:\Users\<you>\AppData\Roaming\JCall.Engineer\FundOS, Linux: ~/.local/share/JCall.Engineer/FundOS/). |
| Database is Read-Only | FundOS does not have permission to write to the database. | Check the filesystem permissions on the database file. |
| Out of Memory | The system ran out of RAM. | Close other applications and try again. |
| Disk Full | There is not enough free space on your hard drive or SSD. | Free up disk space and try again. |
| Internal Error | An unexpected error occurred. | Report this issue on GitHub. |
Software Updates
Future versions of FundOS may update the database schema when new features require it. If that happens, FundOS will show a screen explaining that a migration is needed and give you the opportunity to back up before it proceeds. Back up before installing any update so you have a safe copy regardless.