First update.

db.js

@@ -0,0 +1,68 @@
+const mariadb = require('mariadb');
+
+// 创建一个连接池
+const pool = mariadb.createPool({
+    host: 'localhost',
+    user: 'rc',
+    password: '1q3e@W$R',
+    database: 'Card'
+  });
+  
+  // 获取连接
+  async function getConnection() {
+    let conn;
+    try {
+        conn = await pool.getConnection();
+        console.log("Connected to the database!");
+    } catch (err) {
+        console.error("Error connecting to the database:", err);
+    }
+    return conn;
+  }
+  
+  // async function insertData(conn) {
+  //   const query = "INSERT INTO your_table (column1, column2) VALUES (?, ?)";
+  //   const values = ['value1', 'value2'];
+  //   try {
+  //       const result = await conn.query(query, values);
+  //       console.log(`Inserted with ID: ${result.insertId}`);
+  //   } catch (err) {
+  //       console.error("Error inserting data:", err);
+  //   }
+  // }
+  
+  async function fetchData(conn) {
+    const query = "SELECT * FROM your_table";
+    try {
+        const rows = await conn.query(query);
+        console.log(rows);
+    } catch (err) {
+        console.error("Error fetching data:", err);
+    }
+  }
+  
+  async function isRoomAvailable(conn, roomId) {
+    const query = "SELECT 1 FROM Room WHERE RoomID = ? AND Status = 0 LIMIT 1";
+    try {
+      const rows = await conn.query(query, [roomId]);
+      if (rows.length === 0) {
+        // 不存在或已被占用
+        return false;
+      }
+  
+      // 执行更新
+      const updateQuery = "UPDATE Room SET Status = 1 WHERE RoomID = ?";
+      const result = await conn.query(updateQuery, [roomId]);
+  
+      // 检查是否更新了1行
+      return Number(result.affectedRows) === 1;
+    } catch (err) {
+      console.error("Error checking room availability:", err);
+      return false;
+    }
+  }
+
+  module.exports = {
+    getConnection,
+    isRoomAvailable
+  };