diff --git a/docs/sql/expiry.sql b/docs/sql/expiry.sql
index ba6db88..b24011a 100644
--- a/docs/sql/expiry.sql
+++ b/docs/sql/expiry.sql
@@ -16,10 +16,13 @@ CREATE TABLE IF NOT EXISTS expiry_items (
   quantity INT DEFAULT 1 COMMENT '数量',
   location VARCHAR(50) DEFAULT NULL COMMENT '存放位置（可选）',
   remark VARCHAR(255) DEFAULT NULL COMMENT '备注（可选）',
-  status VARCHAR(20) DEFAULT 'normal' COMMENT '状态：normal/used/expired/discarded',
+  status VARCHAR(20) DEFAULT 'normal' COMMENT '状态：normal/used/discarded（expiring/expired 由业务动态计算）',
   created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
   updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
   deleted_at TIMESTAMP NULL DEFAULT NULL COMMENT '软删除时间',
+  CONSTRAINT chk_expiry_category CHECK (category IN ('food', 'medicine', 'cosmetic', 'other')),
+  CONSTRAINT chk_expiry_quantity CHECK (quantity > 0),
+  CONSTRAINT chk_expiry_status CHECK (status IN ('normal', 'used', 'discarded')),
   
   -- 索引
   INDEX idx_user_expiry (user_id, expiry_date) COMMENT '用户+过期日期索引（最常用查询）',
@@ -34,7 +37,7 @@ CREATE TABLE IF NOT EXISTS expiry_items (
 CREATE TABLE IF NOT EXISTS expiry_user_settings (
   id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY COMMENT '主键ID',
   user_id BIGINT UNSIGNED NOT NULL UNIQUE COMMENT '用户ID（唯一）',
-  remind_days JSON DEFAULT '[7,3,1]' COMMENT '提醒天数数组，例如 [7,3,1]',
+  remind_days JSON DEFAULT (JSON_ARRAY(7,3,1)) COMMENT '提醒天数数组，例如 [7,3,1]',
   created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
   updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
   
diff --git a/docs/sql/reports/expiry_ddl_validation_2026-03-04.md b/docs/sql/reports/expiry_ddl_validation_2026-03-04.md
new file mode 100644
index 0000000..2ee0137
--- /dev/null
+++ b/docs/sql/reports/expiry_ddl_validation_2026-03-04.md
@@ -0,0 +1,26 @@
+# Expiry DDL 验证报告（2026-03-04）
+
+## 结论
+- `expiry_items`、`expiry_user_settings` 两张表结构已齐备。
+- 索引覆盖了用户维度的核心查询路径。
+- 已补充关键约束，降低脏数据进入数据库的风险。
+
+## 本次补充项
+1. `expiry_items` 增加 `CHECK` 约束：
+- `category IN ('food', 'medicine', 'cosmetic', 'other')`
+- `quantity > 0`
+- `status IN ('normal', 'used', 'discarded')`
+
+2. `expiry_user_settings.remind_days` 默认值改为：
+- `JSON_ARRAY(7,3,1)`
+
+## 校验命令
+```sql
+SHOW CREATE TABLE expiry_items;
+SHOW CREATE TABLE expiry_user_settings;
+SHOW INDEX FROM expiry_items;
+SHOW INDEX FROM expiry_user_settings;
+```
+
+## 兼容性说明
+- `CHECK` 约束在 MySQL 8.0+ 生效；若使用低版本，请在应用层保留同等校验逻辑。