diff --git a/database.py b/database.py
index 834f998..9767818 100644
--- a/database.py
+++ b/database.py
@@ -10,6 +10,9 @@ DB_DIR = os.path.join(os.path.expanduser('~'), '.workbuddy', 'data', 'ziwei-powe
 os.makedirs(DB_DIR, exist_ok=True)
 DB_PATH = os.path.join(DB_DIR, 'ziwei_power.db')
 
+# 当前数据库 schema 版本 —— 改表结构时必须 +1 并补迁移逻辑
+CURRENT_SCHEMA_VERSION = 1
+
 
 def get_conn():
     conn = sqlite3.connect(DB_PATH)
@@ -17,18 +20,49 @@ def get_conn():
     return conn
 
 
-def init_db():
-    """初始化数据库表"""
-    conn = get_conn()
+def _get_schema_version(conn):
+    """读取当前数据库的 schema 版本，无表时返回 0"""
     conn.execute('''
-        CREATE TABLE IF NOT EXISTS checkins (
-            id INTEGER PRIMARY KEY AUTOINCREMENT,
-            date TEXT UNIQUE NOT NULL,
-            data TEXT NOT NULL,
-            created_at TEXT NOT NULL,
-            updated_at TEXT NOT NULL
+        CREATE TABLE IF NOT EXISTS schema_version (
+            version INTEGER NOT NULL
         )
     ''')
+    row = conn.execute('SELECT version FROM schema_version').fetchone()
+    return row['version'] if row else 0
+
+
+def _set_schema_version(conn, version):
+    """写入 schema 版本"""
+    conn.execute('DELETE FROM schema_version')
+    conn.execute('INSERT INTO schema_version (version) VALUES (?)', (version,))
+
+
+def init_db():
+    """初始化数据库表 & 自动迁移"""
+    conn = get_conn()
+    current = _get_schema_version(conn)
+
+    # ── 迁移步骤（按版本号递增）────────────────────────
+    if current < 1:
+        # v1: 初始表结构
+        conn.execute('''
+            CREATE TABLE IF NOT EXISTS checkins (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                date TEXT UNIQUE NOT NULL,
+                data TEXT NOT NULL,
+                created_at TEXT NOT NULL,
+                updated_at TEXT NOT NULL
+            )
+        ''')
+
+    # ── 将来加字段/改表在此扩展 ──
+    # if current < 2:
+    #     conn.execute('ALTER TABLE checkins ADD COLUMN tags TEXT DEFAULT ""')
+    #     # 可选：对已有行做数据补全
+    #     conn.execute("UPDATE checkins SET tags = '[]' WHERE tags IS NULL")
+
+    # ── 写入最新版本号 ──
+    _set_schema_version(conn, CURRENT_SCHEMA_VERSION)
     conn.commit()
     conn.close()