Document how a drive can be deleted manually

Closes #360

README.md

@@ -71,6 +71,7 @@ The full TeslaMate documentation is available on [Read the Docs](https://teslama
   - [Environment Variables](https://teslamate.readthedocs.io/en/latest/configuration/environment_variables.html)
 - Maintenance
   - [Backup and Restore](https://teslamate.readthedocs.io/en/latest/maintenance/backup_restore.html)
+  - [Manually fixing data](https://teslamate.readthedocs.io/en/latest/maintenance/manually_fixing_data.html)
 - Development and Contributing
   - [Development](https://teslamate.readthedocs.io/en/latest/development.html)
 

docs/index.rst

@@ -41,6 +41,7 @@ A powerful, self-hosted data logger for your Tesla.
    :caption: Maintenance
 
    maintenance/backup_restore.md
+   maintenance/manually_fixing_data.md
 
 .. toctree::
    :maxdepth: 1

docs/maintenance/manually_fixing_data.md

@@ -0,0 +1,28 @@
+# Manually fixing data
+
+## Docker: Connect to the database container
+
+When using TeslaMate with Docker, you must first connect to the **running** database container before queries can be executed.
+
+```bash
+docker-compose exec database psql teslamate teslamate
+```
+
+## Delete a specific drive
+
+If for some reason a drive was recorded incorrectly, you can delete it manually.
+
+First you need to find out the ID of the drive you want to delete:
+
+- Open the `Drives` dashboard and click on the start date of the drive.
+- The URL will contain the drive id, for example `&var-drive_id=9999`.
+
+Afterwards run the following query:
+
+```sql
+BEGIN;
+UPDATE drives SET start_position_id = NULL, end_position_id = NULL WHERE id = 9999;
+DELETE FROM positions WHERE drive_id = 9999;
+DELETE FROM drives WHERE id = 9999;
+COMMIT;
+```