diff --git a/core/database.py b/core/database.py
index 0ffdd0b..39beae5 100644
--- a/core/database.py
+++ b/core/database.py
@@ -180,6 +180,9 @@ class Database:
         """)
         
         # 赌场游戏会话表
+        # 注意：移除了UNIQUE(chat_id, game_type, status)约束
+        # 因为status='closed'时需要允许多条历史记录
+        # 单场限制通过应用层逻辑（get_any_active_casino_session）保证
         cursor.execute("""
             CREATE TABLE IF NOT EXISTS casino_sessions (
                 id INTEGER PRIMARY KEY AUTOINCREMENT,
@@ -192,11 +195,92 @@ class Database:
                 house_fee REAL DEFAULT 0.05,
                 status TEXT DEFAULT 'open',
                 created_at INTEGER NOT NULL,
-                settled_at INTEGER,
-                UNIQUE(chat_id, game_type, status)
+                settled_at INTEGER
             )
         """)
         
+        # 迁移：如果表已存在且有UNIQUE约束，需要重建表
+        # 检查是否已有旧表（通过检查是否有UNIQUE约束的索引）
+        try:
+            # 尝试查询表结构，检查是否有UNIQUE约束相关的索引
+            cursor.execute("SELECT sql FROM sqlite_master WHERE type='table' AND name='casino_sessions'")
+            old_sql = cursor.fetchone()
+            if old_sql and 'UNIQUE(chat_id, game_type, status)' in old_sql[0]:
+                # 需要重建表以移除UNIQUE约束
+                logger.info("检测到旧版本的casino_sessions表，需要重建以移除UNIQUE约束")
+                # 禁用外键检查（SQLite默认可能未启用，但为了安全）
+                cursor.execute("PRAGMA foreign_keys=OFF")
+                # 创建临时表
+                cursor.execute("""
+                    CREATE TABLE IF NOT EXISTS casino_sessions_new (
+                        id INTEGER PRIMARY KEY AUTOINCREMENT,
+                        chat_id INTEGER NOT NULL,
+                        game_type TEXT NOT NULL,
+                        banker_id INTEGER NOT NULL,
+                        min_bet INTEGER NOT NULL,
+                        max_bet INTEGER NOT NULL,
+                        multiplier REAL NOT NULL,
+                        house_fee REAL DEFAULT 0.05,
+                        status TEXT DEFAULT 'open',
+                        created_at INTEGER NOT NULL,
+                        settled_at INTEGER,
+                        current_phase TEXT DEFAULT 'betting',
+                        blackjack_multiplier REAL DEFAULT 1.5
+                    )
+                """)
+                # 复制所有数据（包括历史记录）
+                # 检查旧表是否有新字段
+                old_columns = [row[1] for row in cursor.execute("PRAGMA table_info(casino_sessions)").fetchall()]
+                has_current_phase = 'current_phase' in old_columns
+                has_blackjack_multiplier = 'blackjack_multiplier' in old_columns
+                
+                if has_current_phase and has_blackjack_multiplier:
+                    # 旧表已有新字段，直接复制所有列
+                    cursor.execute("""
+                        INSERT INTO casino_sessions_new 
+                        SELECT id, chat_id, game_type, banker_id, min_bet, max_bet, 
+                               multiplier, house_fee, status, created_at, settled_at,
+                               current_phase, blackjack_multiplier
+                        FROM casino_sessions
+                    """)
+                elif has_current_phase:
+                    # 只有current_phase字段
+                    cursor.execute("""
+                        INSERT INTO casino_sessions_new 
+                        SELECT id, chat_id, game_type, banker_id, min_bet, max_bet, 
+                               multiplier, house_fee, status, created_at, settled_at,
+                               current_phase, 1.5 as blackjack_multiplier
+                        FROM casino_sessions
+                    """)
+                elif has_blackjack_multiplier:
+                    # 只有blackjack_multiplier字段
+                    cursor.execute("""
+                        INSERT INTO casino_sessions_new 
+                        SELECT id, chat_id, game_type, banker_id, min_bet, max_bet, 
+                               multiplier, house_fee, status, created_at, settled_at,
+                               'betting' as current_phase, blackjack_multiplier
+                        FROM casino_sessions
+                    """)
+                else:
+                    # 都没有新字段，使用默认值
+                    cursor.execute("""
+                        INSERT INTO casino_sessions_new 
+                        SELECT id, chat_id, game_type, banker_id, min_bet, max_bet, 
+                               multiplier, house_fee, status, created_at, settled_at,
+                               'betting' as current_phase, 1.5 as blackjack_multiplier
+                        FROM casino_sessions
+                    """)
+                # 删除旧表
+                cursor.execute("DROP TABLE casino_sessions")
+                # 重命名新表
+                cursor.execute("ALTER TABLE casino_sessions_new RENAME TO casino_sessions")
+                # 重新启用外键检查
+                cursor.execute("PRAGMA foreign_keys=ON")
+                logger.info("成功重建casino_sessions表，移除UNIQUE约束")
+        except Exception as e:
+            # 如果迁移失败，记录日志但不影响正常运行
+            logger.warning(f"迁移casino_sessions表时出现错误（可能表结构已更新）: {e}")
+        
         # 21点手牌表
         cursor.execute("""
             CREATE TABLE IF NOT EXISTS casino_blackjack_hands (