diff --git a/2207/MySQL数据库操作综合练习题答案.md b/2207/MySQL数据库操作综合练习题答案.md
index 22cce39..87370a8 100644
--- a/2207/MySQL数据库操作综合练习题答案.md
+++ b/2207/MySQL数据库操作综合练习题答案.md
@@ -84,3 +84,35 @@ WHERE death IS NOT NULL;
 TRUNCATE pet;
 ```
 
+### 练习三
+
+```sql
+#1.创建数据库
+CREATE DATABASE test_compay DEFAULT CHARACTER SET utf8;
+
+#2.创建表
+CREATE TABLE department(
+	depid INT PRIMARY KEY AUTO_INCREMENT,
+	depname VARCHAR(20) NOT NULL,
+	deinfo VARCHAR(50)
+);
+CREATE TABLE employee(
+	empid INT PRIMARY KEY AUTO_INCREMENT,
+	`name` VARCHAR(20) NOT NULL,
+	sex CHAR(1) NOT NULL DEFAULT '男',
+	title VARCHAR(20) NOT NULL,
+	birthday DATE NOT NULL,
+	depid INT,
+	CONSTRAINT fk_eid_did FOREIGN KEY(depid) REFERENCES department(depid)
+);
+CREATE TABLE salary(
+	empid INT,
+	basesalary DECIMAL(10, 2),
+	titleSalary DECIMAL(10, 2),
+	decuction DECIMAL(10, 2)
+);
+#3添加外键并设置级联更新、级联删除
+ALTER TABLE salary ADD CONSTRAINT fk_sal_eid FOREIGN KEY(empid) 
+REFERENCES employee(empid) ON UPDATE CASCADE ON DELETE CASCADE;
+```
+