diff --git a/src/modules/database/sqlocal/databaseProvider.ts b/src/modules/database/sqlocal/databaseProvider.ts
index b36ed25..142499a 100644
--- a/src/modules/database/sqlocal/databaseProvider.ts
+++ b/src/modules/database/sqlocal/databaseProvider.ts
@@ -8,8 +8,9 @@ export class DatabaseProvider {
 	constructor(private app: App) { }
 
 	get prefix() {
+		const appId = ((this.app as any).appId ?? '').replace(/[^a-zA-Z0-9_-]/g, '_');
 		const filename = `sqlseal_1__` +
-			sanitise(this.app.vault.getName()) + "___" + (this.app as any).appId;
+			sanitise(this.app.vault.getName()) + "___" + appId;
 		return filename;
 	}