docs(HedgeDoc): Add documentation to debug

hedgedoc/README.md

@@ -21,6 +21,23 @@ Lancer le service :
 docker-compose up -d
 ```
 
+## Debug
+
+### Se connecter à la base de données
+
+```shell
+. .env
+docker exec -it $POSTGRES_CONTAINER_NAME psql $POSTGRES_DB -U $POSTGRES_USER
+```
+
+### Traitement des notes vides
+
+```
+SELECT count(*) FROM public."Notes" WHERE content = '';
+SELECT * FROM public."Notes" WHERE content = '';
+DELETE FROM public."Notes" WHERE content = '';
+```
+
 ## Liens
 
 - [Site officiel][website]