added docker-compose.yml in root, added backend/README.md

backend/README.md

@@ -0,0 +1,27 @@
+## Database Schema
+
+```mermaid
+erDiagram
+    user {
+        string name PK
+    }
+
+    game {
+        serial game_id PK
+        int score
+        time playtime
+        date date
+        string username FK
+    }
+
+    user ||--O{ game : "played"
+
+    user_data {
+        string username PK
+        int highscore
+        int total_score
+        int total_playtime
+        int average_score
+        int games_played
+    }
+```

docker-compose.yml

@@ -0,0 +1,12 @@
+version: '3.1'
+
+services:
+  db:
+    build: backend/db
+    environment:
+      POSTGRES_DB: rr
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: postgres
+    volumes:
+      - ./pgdata:/var/lib/postgresql/data
+