v2.3修复

backend/routes/upgrade.py

@@ -37,6 +37,64 @@ ALL_VERSIONS = {
     '2.3': 'v2.3.sql',
 }
 
+# 版本特征标记（按优先级从高到低）
+VERSION_MARKERS = [
+    ('2.0', 'students', 'dormitory_number'),
+    ('1.8', 'conduct_records', 'related_type'),
+    ('1.7', 'subjects', 'sort_order'),
+]
+
+
+async def _detect_current_version() -> str:
+    """检测当前数据库版本，优先从 system_settings 读取，否则通过列特征推断"""
+    # 1. 尝试从 system_settings 读取 db_version
+    try:
+        row = await execute_query(
+            "SELECT setting_value FROM system_settings WHERE setting_key = 'db_version'"
+        )
+        if row:
+            return row[0]['setting_value']
+    except Exception as e:
+        logger.warning(f"查询 system_settings 表失败，将通过列特征推断版本: {e}")
+
+    # 2. 通过列特征推断版本
+    inferred_version = '1.0'
+    for version, table, column in VERSION_MARKERS:
+        try:
+            result = await execute_query(
+                "SELECT COUNT(*) as cnt FROM INFORMATION_SCHEMA.COLUMNS "
+                "WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = %s AND COLUMN_NAME = %s",
+                (table, column)
+            )
+            if result and result[0]['cnt'] > 0:
+                inferred_version = version
+                break
+        except Exception as e:
+            logger.warning(f"检查列特征失败 ({table}.{column}): {e}")
+
+    logger.info(f"通过列特征推断数据库版本为: {inferred_version}")
+
+    # 3. 确保 system_settings 表存在并写入推断版本
+    try:
+        await execute_update(
+            "CREATE TABLE IF NOT EXISTS `system_settings` ("
+            "`setting_key` VARCHAR(50) PRIMARY KEY,"
+            "`setting_value` VARCHAR(255) NOT NULL,"
+            "`updated_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP"
+            ") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci"
+        )
+        await execute_update(
+            "INSERT INTO system_settings (setting_key, setting_value) VALUES ('db_version', %s) "
+            "ON DUPLICATE KEY UPDATE setting_value = %s",
+            (inferred_version, inferred_version)
+        )
+        logger.info(f"已将推断版本 {inferred_version} 写入 system_settings")
+    except Exception as e:
+        logger.error(f"写入推断版本失败: {e}")
+
+    return inferred_version
+
+
 @router.get("/check")
 async def check_upgrade(request: Request):
     """检查数据库版本是否需要升级"""
@@ -51,16 +109,8 @@ async def check_upgrade(request: Request):
     if not is_teacher:
         return error_response(message="仅班主任可执行升级操作", code=403)
     
-    # 检测当前数据库版本
-    current_version = '0.0.0'
-    try:
-        row = await execute_query(
-            "SELECT setting_value FROM system_settings WHERE setting_key = 'db_version'"
-        )
-        if row:
-            current_version = row[0]['setting_value']
-    except Exception:
-        pass  # 表不存在时使用默认值
+    # 检测当前数据库版本（支持自动推断）
+    current_version = await _detect_current_version()
     
     # 读取目标版本（从 VERSION 文件）
     version_file = os.path.join(os.path.dirname(os.path.dirname(__file__)), '..', 'VERSION')