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Troubleshooting and FAQ ​

Symptoms and questions, each with its cause and fix.

Connecting ​

"Connection failed" for a server database ​

The text after Connection failed: comes from the database. Check, in this order:

  1. Host and Port. The defaults are 3306 for MySQL / MariaDB, 5432 for PostgreSQL and 27017 for MongoDB.
  2. That the server is running and reachable from your computer. Servers often accept connections only from the same machine until they are configured otherwise, and a firewall may block the port.
  3. The Database name. PostgreSQL needs one.
  4. Use SSL / TLS. Turn it on if the server requires encrypted connections, and off if the server does not offer them.

The app keeps asking for the password ​

The server rejected the sign-in, so the app offers another try and shows the server's message. Check the user name in the connection, and that this user may connect from your computer. Select Cancel to stop.

"File not found" for a SQLite connection ​

The file was moved, renamed or deleted, or it is on a drive that is not connected. Select Edit in the connection's menu and pick the file again. The app opens existing files only. It does not create a database.

A SQLite file asks for a password I never set ​

The file is not an ordinary SQLite database. Either it is encrypted with SQLCipher, and you need the password from whoever created it, or it is not a SQLite database at all.

LMDB will not open ​

  • If the message mentions the liblmdb library, install it: sudo apt install liblmdb0.
  • Path not found: the folder in the connection no longer exists.
  • A message that starts with mdb_env_open: the folder is not an LMDB database, or you do not have permission to read it. Point the connection at the folder that contains data.mdb.

Browsing ​

A table I expect is missing from the list ​

  • Select the refresh button in the title bar. The list does not update by itself.
  • Clear the filter box above the list.
  • For PostgreSQL, only tables in the public schema are listed. Query other schemas from the Query tab.
  • Check that the connection opens the right database.

The row count and the grid disagree ​

The count is read once per table or search. If other programs are changing the data, select the refresh button in the toolbar.

Text in the grid is cut off ​

The grid shows the first 200 characters of a value. Click the row to see the whole value in the Edit row dialog, then select Cancel.

Editing ​

"This row cannot be edited (no row identifier)" ​

The app cannot tell this row apart from others. It happens for SQLite views and tables created WITHOUT ROWID. Use an UPDATE or DELETE statement in the Query tab.

"Insert failed" or "Update failed" ​

The database refused the change, and the rest of the message says why. Typical reasons: a required column was left empty, a value has the wrong type, a unique value already exists, or your user lacks permission.

An auto-numbered column fails on insert in PostgreSQL ​

The Insert into dialog sends a value for every column. Ticking NULL for an auto-numbered column works in SQLite and MySQL, but PostgreSQL rejects it. In PostgreSQL, insert from the Query tab and leave the column out:

sql
INSERT INTO people (name, city) VALUES ('Dev', 'Pune');

"Environment was opened read-only" (LMDB) ​

The app could not open the LMDB folder for writing, so it opened it read-only. Check the folder's permissions, and whether another program has locked it.

I changed or deleted the wrong row. Can I undo it? ​

No. Changes are written immediately. Restore the value from a backup, or type it back if you know it. Take a backup before editing data that matters. See Edit data safely.

Queries ​

"Command must be a JSON object" (MongoDB) ​

The Query tab for MongoDB takes a command as strict JSON, for example {"find": "users", "limit": 10}. Use double quotes around keys and text. Shell commands such as db.users.find() are not accepted.

My query returned so many rows that the app became slow ​

The Query tab loads the whole result into one grid. Add a LIMIT, or a more selective WHERE.

A new table does not appear after CREATE TABLE ​

Select the refresh button in the title bar.

Export and backup ​

Does Export CSV save only the page I see? ​

No. On the Data tab it saves every row that matches the current search. On the Query tab it saves the whole result.

"Backup failed" ​

The rest of the message gives the reason. Check that you can write to the folder you chose and that it has enough free space. For server databases, your user must be allowed to read every table.

How do I restore a backup? ​

With the database's own tools. The app has no restore button. See Restore a backup.

Passwords and privacy ​

Where are my connections and passwords stored? ​

In a JSON file on your computer, listed in the Reference. Saved passwords are in plain text. To keep a password out of the file, turn on Ask for the password every time for that connection.

I forgot the password of an encrypted SQLite file ​

It cannot be recovered. If you have a backup made before the file was encrypted, or one whose password you remember, use that.

Does the app send my data anywhere? ​

The app connects only to the databases you set up. It has no account and no cloud service.

Is there a Windows or macOS version? ​

Release 1.0.0 is published for Linux (amd64, .deb) only.

Get help ​

Report a problem on the Database Manager issues page. Say which database type you use and copy the exact error message. Remove host names, user names and passwords before you post.

Next steps ​