Refactor: Update controllers and services for improved functionality and add new SQL queries

src/main/java/com/grtsinry43/bookmanagement/controller/BookController.java

@@ -16,10 +16,7 @@ import org.springframework.web.bind.annotation.*;
 import java.util.List;
 
 /**
- * <p>
+ * 书籍控制器
- * 前端控制器
- * </p>
- *
  * @author grtsinry43
  * @since 2025-05-19
  */
@@ -48,7 +45,6 @@ public class BookController {
     }
 
     @GetMapping("/search/title")
-    @AuthCheck(requiredRole = UserRole.USER)
     public ApiResponse<PageResponse<List<BookVO>>> searchBooksByTitle(@RequestParam String title,
                                                                       @RequestParam(defaultValue = "1") int pageNum,
                                                                       @RequestParam(defaultValue = "10") int pageSize) {
@@ -57,7 +53,6 @@ public class BookController {
     }
 
     @GetMapping("/search/author")
-    @AuthCheck(requiredRole = UserRole.USER)
     public ApiResponse<PageResponse<List<BookVO>>> searchBooksByAuthor(@RequestParam String authorName,
                                                                        @RequestParam(defaultValue = "1") int pageNum,
                                                                        @RequestParam(defaultValue = "10") int pageSize) {
@@ -66,7 +61,6 @@ public class BookController {
     }
 
     @GetMapping("/search/publisher")
-    @AuthCheck(requiredRole = UserRole.USER)
     public ApiResponse<PageResponse<List<BookVO>>> searchBooksByPublisher(@RequestParam String publisherName,
                                                                           @RequestParam(defaultValue = "1") int pageNum,
                                                                           @RequestParam(defaultValue = "10") int pageSize) {

src/main/java/com/grtsinry43/bookmanagement/controller/OrdersController.java

@@ -13,6 +13,12 @@ import org.springframework.web.bind.annotation.*;
 
 import java.util.List;
 
+/**
+ * 订单控制器
+ *
+ * @author grtsinry43
+ * @since 2025-05-19
+ */
 @RestController
 @RequestMapping("/orders")
 public class OrdersController {

src/main/java/com/grtsinry43/bookmanagement/controller/PublisherController.java

@@ -9,9 +9,7 @@ import org.springframework.web.bind.annotation.*;
 import java.util.List;
 
 /**
- * <p>
+ * 出版社控制器
- *  前端控制器
- * </p>
  *
  * @author grtsinry43
  * @since 2025-05-19

src/main/java/com/grtsinry43/bookmanagement/controller/ReaderController.java

@@ -11,6 +11,8 @@ import com.grtsinry43.bookmanagement.entity.Reader;
 import com.grtsinry43.bookmanagement.service.ReaderService;
 import com.grtsinry43.bookmanagement.util.JwtUtil;
 import com.grtsinry43.bookmanagement.vo.ReaderVO;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
 import org.springframework.beans.BeanUtils;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.web.bind.annotation.*;
@@ -21,9 +23,7 @@ import java.util.Map;
 import java.util.stream.Collectors;
 
 /**
- * <p>
+ * 读者控制器
- * 前端控制器
- * </p>
  *
  * @author grtsinry43
  * @since 2025-05-19
@@ -63,7 +63,7 @@ public class ReaderController {
 
     @PostMapping("/login")
     @AuthCheck(requiredRole = UserRole.NOT_LOGIN)
-    public ApiResponse<Map<String, Object>> login(@RequestBody LoginRequest loginRequest) {
+    public ApiResponse<ReaderVO> login(@RequestBody LoginRequest loginRequest, HttpServletResponse response) {
         if (loginRequest.getUsername() == null || loginRequest.getPassword() == null ||
                 loginRequest.getUsername().trim().isEmpty() || loginRequest.getPassword().isEmpty()) {
             throw new BusinessException(ErrorCode.PARAMS_ERROR);
@@ -72,11 +72,9 @@ public class ReaderController {
         Reader loggedInReader = readerService.login(loginRequest.getUsername(), loginRequest.getPassword());
         String token = JwtUtil.generateToken(loggedInReader.getReaderId().toString());
 
-        Map<String, Object> responseData = new HashMap<>();
+        response.setHeader("Authorization", token);
-        responseData.put("token", token);
-        responseData.put("user", convertToReaderVO(loggedInReader));
 
-        return ApiResponse.success(responseData);
+        return ApiResponse.success(convertToReaderVO(loggedInReader));
     }
 
     @GetMapping("/admin/all")

src/main/java/com/grtsinry43/bookmanagement/service/impl/BookServiceImpl.java

@@ -139,6 +139,7 @@ public class BookServiceImpl extends ServiceImpl<BookMapper, Book> implements Bo
             book1.setPublisherId(publisherId);
         }
         BeanUtils.copyProperties(book, book1);
+        book1.setAuthor(String.join(",", book.getAuthors()));
         bookMapper.insert(book1);
         resetBookAuthors(book1.getBookId(), book.getAuthors());
         return buildBookVO(book1);

src/main/java/com/grtsinry43/bookmanagement/service/impl/OrdersServiceImpl.java

@@ -50,6 +50,7 @@ public class OrdersServiceImpl extends ServiceImpl<OrdersMapper, Orders> impleme
     public OrderVO createOrder(OrderCreateDTO orderCreateDTO, Integer userId) {
         Orders order = new Orders();
         order.setOrderDate(LocalDateTime.now());
+        order.setReaderId(userId);
         order.setStatus("PENDING");
         BigDecimal totalAmount = BigDecimal.ZERO;
         List<OrderItem> items = new ArrayList<>();

src/main/java/com/grtsinry43/bookmanagement/service/impl/ReaderServiceImpl.java

@@ -32,6 +32,7 @@ public class ReaderServiceImpl extends ServiceImpl<ReaderMapper, Reader> impleme
         this.passwordEncoder = new BCryptPasswordEncoder();
     }
 
+
     @Override
     public Reader getReaderById(Integer readerId) {
         if (readerId == null) {

src/main/resources/application.properties

@@ -10,4 +10,4 @@ server.port=8080
 
 mybatis.type-aliases-package=com.grtsinry43.bookmanagement.entity
 mybatis.configuration.map-underscore-to-camel-case=true
-logging.level.com.grtsinry43.bookmanagement.mapper=DEBUG
+#logging.level.com.grtsinry43.bookmanagement.mapper=DEBUG

src/main/resources/mapper/AuthorMapper.xml

@@ -2,4 +2,38 @@
 <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
 <mapper namespace="com.grtsinry43.bookmanagement.mapper.AuthorMapper">
 
+    <!-- 1. 查询所有作者（单表+ORDER BY） -->
+    <select id="findAllAuthors" resultType="com.grtsinry43.bookmanagement.entity.Author">
+        SELECT * FROM author ORDER BY name
+    </select>
+
+    <!-- 2. 查询名字包含关键字的作者（单表+LIKE） -->
+    <select id="findByNameLike" resultType="com.grtsinry43.bookmanagement.entity.Author">
+        SELECT * FROM author WHERE name LIKE CONCAT('%', #{name}, '%')
+    </select>
+
+    <!-- 3. 查询每位作者的图书数量（连接+GROUP BY+COUNT） -->
+    <select id="countBooksByAuthor" resultType="map">
+        SELECT a.author_id, a.name, COUNT(ba.book_id) AS book_count
+        FROM author a
+        LEFT JOIN book_author ba ON a.author_id = ba.author_id
+        GROUP BY a.author_id, a.name
+        ORDER BY book_count DESC
+    </select>
+
+    <!-- 4. 查询没有图书的作者（嵌套NOT EXISTS） -->
+    <select id="findAuthorsWithoutBooks" resultType="com.grtsinry43.bookmanagement.entity.Author">
+        SELECT * FROM author a WHERE NOT EXISTS (
+            SELECT 1 FROM book_author ba WHERE ba.author_id = a.author_id
+        )
+    </select>
+
+    <!-- 5. 查询指定一组ID的作者（IN集合查询） -->
+    <select id="findByIds" resultType="com.grtsinry43.bookmanagement.entity.Author">
+        SELECT * FROM author WHERE author_id IN
+        <foreach collection="ids" item="id" open="(" separator="," close=")">
+            #{id}
+        </foreach>
+    </select>
+
 </mapper>

src/main/resources/mapper/BookMapper.xml

@@ -3,33 +3,112 @@
 <mapper namespace="com.grtsinry43.bookmanagement.mapper.BookMapper">
 
     <select id="findById" resultType="com.grtsinry43.bookmanagement.entity.Book">
-        SELECT * FROM book WHERE book_id = #{bookId}
+        SELECT *
+        FROM book
+        WHERE book_id = #{bookId}
     </select>
 
     <select id="findAll" resultType="com.grtsinry43.bookmanagement.entity.Book">
-        SELECT * FROM book
+        SELECT *
+        FROM book
     </select>
 
     <select id="findByTitle" resultType="com.grtsinry43.bookmanagement.entity.Book">
-        SELECT * FROM book WHERE title LIKE CONCAT('%', #{title}, '%')
+        SELECT *
+        FROM book
+        WHERE title LIKE CONCAT('%', #{title}, '%')
     </select>
 
     <select id="findByAuthor" resultType="com.grtsinry43.bookmanagement.entity.Book">
-        SELECT b.* FROM book b
+        SELECT b.*
+        FROM book b
                  JOIN book_author ba ON b.book_id = ba.book_id
                  JOIN author a ON ba.author_id = a.author_id
         WHERE a.name LIKE CONCAT('%', #{authorName}, '%')
     </select>
 
     <select id="findByPublisher" resultType="com.grtsinry43.bookmanagement.entity.Book">
-        SELECT b.* FROM book b
+        SELECT b.*
+        FROM book b
                  JOIN publisher p ON b.publisher_id = p.publisher_id
         WHERE p.name LIKE CONCAT('%', #{publisherName}, '%')
     </select>
 
-    <insert id="insert" parameterType="com.grtsinry43.bookmanagement.entity.Book" useGeneratedKeys="true" keyProperty="bookId">
+    <!-- 1. 查询所有库存为0的图书（单表+ORDER BY） -->
-        INSERT INTO book (title, isbn, price, stock, publish_date, publisher_id)
+    <select id="findOutOfStockBooks" resultType="com.grtsinry43.bookmanagement.entity.Book">
-        VALUES (#{title}, #{isbn}, #{price}, #{stock}, #{publishDate}, #{publisherId})
+        SELECT * FROM book WHERE stock = 0 ORDER BY publish_date DESC
+    </select>
+
+    <!-- 2. 查询每个出版社的图书数量（连接+GROUP BY+聚合） -->
+    <select id="countBooksByPublisher" resultType="map">
+        SELECT p.name AS publisher_name, COUNT(b.book_id) AS book_count
+        FROM book b
+        JOIN publisher p ON b.publisher_id = p.publisher_id
+        GROUP BY p.name
+        ORDER BY book_count DESC
+    </select>
+
+    <!-- 3. 查询价格高于平均价格的图书（嵌套查询+单表） -->
+    <select id="findBooksAboveAveragePrice" resultType="com.grtsinry43.bookmanagement.entity.Book">
+        SELECT * FROM book WHERE price > (SELECT AVG(price) FROM book)
+    </select>
+
+    <!-- 4. 查询指定一组ISBN的图书（IN集合查询） -->
+    <select id="findByIsbns" resultType="com.grtsinry43.bookmanagement.entity.Book">
+        SELECT * FROM book WHERE isbn IN
+        <foreach collection="isbns" item="isbn" open="(" separator="," close=")">
+            #{isbn}
+        </foreach>
+    </select>
+
+    <!-- 5. 查询有多位作者的图书（连接+GROUP BY+HAVING） -->
+    <select id="findBooksWithMultipleAuthors" resultType="com.grtsinry43.bookmanagement.entity.Book">
+        SELECT b.*
+        FROM book b
+        JOIN book_author ba ON b.book_id = ba.book_id
+        GROUP BY b.book_id
+        HAVING COUNT(ba.author_id) > 1
+    </select>
+
+    <!-- 6. 查询每个作者的图书总价（连接+GROUP BY+SUM） -->
+    <select id="sumBookPriceByAuthor" resultType="map">
+        SELECT a.name AS author_name, SUM(b.price) AS total_price
+        FROM book b
+        JOIN book_author ba ON b.book_id = ba.book_id
+        JOIN author a ON ba.author_id = a.author_id
+        GROUP BY a.name
+    </select>
+
+    <!-- 7. 查询未被任何订单购买过的图书（嵌套NOT EXISTS） -->
+    <select id="findBooksNeverOrdered" resultType="com.grtsinry43.bookmanagement.entity.Book">
+        SELECT * FROM book b WHERE NOT EXISTS (
+            SELECT 1 FROM order_item oi WHERE oi.book_id = b.book_id
+        )
+    </select>
+
+    <!-- 8. 查询最近出版的5本图书（单表+ORDER BY+LIMIT） -->
+    <select id="findLatestBooks" resultType="com.grtsinry43.bookmanagement.entity.Book">
+        SELECT * FROM book ORDER BY publish_date DESC LIMIT 5
+    </select>
+
+    <!-- 9. 查询价格在指定区间的图书（BETWEEN集合查询） -->
+    <select id="findBooksByPriceRange" resultType="com.grtsinry43.bookmanagement.entity.Book">
+        SELECT * FROM book WHERE price BETWEEN #{minPrice} AND #{maxPrice}
+    </select>
+
+    <!-- 10. 查询每本书的销量（连接+GROUP BY+SUM） -->
+    <select id="findBookSales" resultType="map">
+        SELECT b.book_id, b.title, SUM(oi.quantity) AS total_sales
+        FROM book b
+        JOIN order_item oi ON b.book_id = oi.book_id
+        GROUP BY b.book_id, b.title
+        ORDER BY total_sales DESC
+    </select>
+
+    <insert id="insert" parameterType="com.grtsinry43.bookmanagement.entity.Book" useGeneratedKeys="true"
+            keyProperty="bookId">
+        INSERT INTO book (title, isbn, price, stock, publish_date, publisher_id, author)
+        VALUES (#{title}, #{isbn}, #{price}, #{stock}, #{publishDate}, #{publisherId}, #{author})
     </insert>
 
     <update id="update" parameterType="com.grtsinry43.bookmanagement.entity.Book">
@@ -44,6 +123,8 @@
     </update>
 
     <delete id="delete">
-        DELETE FROM book WHERE book_id = #{bookId}
+        DELETE
+        FROM book
+        WHERE book_id = #{bookId}
     </delete>
 </mapper>

src/main/resources/mapper/OrderItemMapper.xml

@@ -11,6 +11,38 @@
         VALUES (#{orderId}, #{bookId}, #{quantity}, #{unitPrice})
     </insert>
 
+    <!-- 1. 查询某本书的所有订单明细（单表+ORDER BY） -->
+    <select id="findByBookId" resultType="com.grtsinry43.bookmanagement.entity.OrderItem">
+        SELECT * FROM order_item WHERE book_id = #{bookId} ORDER BY order_id DESC
+    </select>
+
+    <!-- 2. 查询订单明细中数量大于指定值的记录（单表+条件） -->
+    <select id="findByQuantityGreaterThan" resultType="com.grtsinry43.bookmanagement.entity.OrderItem">
+        SELECT * FROM order_item WHERE quantity > #{quantity}
+    </select>
+
+    <!-- 3. 查询每本书的总售出数量（连接+GROUP BY+SUM） -->
+    <select id="sumQuantityByBook" resultType="map">
+        SELECT b.title, SUM(oi.quantity) AS total_quantity
+        FROM order_item oi
+        JOIN book b ON oi.book_id = b.book_id
+        GROUP BY b.title
+        ORDER BY total_quantity DESC
+    </select>
+
+    <!-- 4. 查询某订单下所有图书的单价（连接查询） -->
+    <select id="findBookUnitPricesByOrderId" resultType="map">
+        SELECT b.title, oi.unit_price
+        FROM order_item oi
+        JOIN book b ON oi.book_id = b.book_id
+        WHERE oi.order_id = #{orderId}
+    </select>
+
+    <!-- 5. 查询未被任何订单明细引用的图书ID（嵌套NOT IN） -->
+    <select id="findBookIdsNotInOrderItems" resultType="int">
+        SELECT book_id FROM book WHERE book_id NOT IN (SELECT book_id FROM order_item)
+    </select>
+
     <!-- Example for batch insert -->
     <!--
     <insert id="insertBatch" parameterType="java.util.List">

src/main/resources/mapper/OrdersMapper.xml

@@ -23,4 +23,72 @@
         UPDATE orders SET status = #{status} WHERE order_id = #{orderId}
     </update>
 
+    <!-- 1. 查询所有已完成订单（单表+ORDER BY） -->
+    <select id="findCompletedOrders" resultType="com.grtsinry43.bookmanagement.entity.Orders">
+        SELECT * FROM orders WHERE status = 'COMPLETED' ORDER BY order_date DESC
+    </select>
+
+    <!-- 2. 查询每个用户的订单总金额（连接+GROUP BY+SUM） -->
+    <select id="sumOrderAmountByReader" resultType="map">
+        SELECT r.reader_id, r.username, SUM(o.total_amount) AS total_amount
+        FROM orders o
+        JOIN reader r ON o.reader_id = r.reader_id
+        GROUP BY r.reader_id, r.username
+        ORDER BY total_amount DESC
+    </select>
+
+    <!-- 3. 查询金额大于平均值的订单（嵌套查询） -->
+    <select id="findOrdersAboveAverageAmount" resultType="com.grtsinry43.bookmanagement.entity.Orders">
+        SELECT * FROM orders WHERE total_amount > (SELECT AVG(total_amount) FROM orders)
+    </select>
+
+    <!-- 4. 查询指定状态集合的订单（IN集合查询） -->
+    <select id="findByStatuses" resultType="com.grtsinry43.bookmanagement.entity.Orders">
+        SELECT * FROM orders WHERE status IN
+        <foreach collection="statuses" item="status" open="(" separator="," close=")">
+            #{status}
+        </foreach>
+    </select>
+
+    <!-- 5. 查询没有订单明细的订单（嵌套NOT EXISTS） -->
+    <select id="findOrdersWithoutItems" resultType="com.grtsinry43.bookmanagement.entity.Orders">
+        SELECT * FROM orders o WHERE NOT EXISTS (
+            SELECT 1 FROM order_item oi WHERE oi.order_id = o.order_id
+        )
+    </select>
+
+    <!-- 6. 查询每月订单数量（聚合+GROUP BY） -->
+    <select id="countOrdersByMonth" resultType="map">
+        SELECT TO_CHAR(order_date, 'YYYY-MM') AS month, COUNT(*) AS order_count
+        FROM orders
+        GROUP BY TO_CHAR(order_date, 'YYYY-MM')
+        ORDER BY month DESC
+    </select>
+
+    <!-- 7. 查询最近一周的订单（单表+时间区间） -->
+    <select id="findOrdersInLastWeek" resultType="com.grtsinry43.bookmanagement.entity.Orders">
+        SELECT * FROM orders WHERE order_date >= NOW() - INTERVAL '7 days' ORDER BY order_date DESC
+    </select>
+
+    <!-- 8. 查询订单金额在指定区间的订单（BETWEEN集合查询） -->
+    <select id="findOrdersByAmountRange" resultType="com.grtsinry43.bookmanagement.entity.Orders">
+        SELECT * FROM orders WHERE total_amount BETWEEN #{minAmount} AND #{maxAmount}
+    </select>
+
+    <!-- 9. 查询每个状态的订单数量（聚合+GROUP BY） -->
+    <select id="countOrdersByStatus" resultType="map">
+        SELECT status, COUNT(*) AS order_count
+        FROM orders
+        GROUP BY status
+    </select>
+
+    <!-- 10. 查询有订单但未支付的用户（连接+嵌套EXISTS） -->
+    <select id="findReadersWithUnpaidOrders" resultType="com.grtsinry43.bookmanagement.entity.Reader">
+        SELECT DISTINCT r.*
+        FROM reader r
+        WHERE EXISTS (
+            SELECT 1 FROM orders o WHERE o.reader_id = r.reader_id AND o.status = 'UNPAID'
+        )
+    </select>
+
 </mapper>

src/main/resources/mapper/PublisherMapper.xml

@@ -30,4 +30,42 @@
         DELETE FROM publisher WHERE publisher_id = #{publisherId}
     </delete>
 
+    <!-- 1. 查询所有含有指定地址的出版社（单表+LIKE+ORDER BY） -->
+    <select id="findByAddressLike" resultType="com.grtsinry43.bookmanagement.entity.Publisher">
+        SELECT * FROM publisher WHERE address LIKE CONCAT('%', #{address}, '%') ORDER BY name
+    </select>
+
+    <!-- 2. 查询出版图书数量大于5的出版社（连接+GROUP BY+HAVING） -->
+    <select id="findPublishersWithManyBooks" resultType="com.grtsinry43.bookmanagement.entity.Publisher">
+        SELECT p.*
+        FROM publisher p
+        JOIN book b ON p.publisher_id = b.publisher_id
+        GROUP BY p.publisher_id
+        HAVING COUNT(b.book_id) > 5
+    </select>
+
+    <!-- 3. 查询没有出版任何图书的出版社（嵌套NOT EXISTS） -->
+    <select id="findPublishersWithoutBooks" resultType="com.grtsinry43.bookmanagement.entity.Publisher">
+        SELECT * FROM publisher p WHERE NOT EXISTS (
+            SELECT 1 FROM book b WHERE b.publisher_id = p.publisher_id
+        )
+    </select>
+
+    <!-- 4. 查询指定一组ID的出版社（IN集合查询） -->
+    <select id="findByIds" resultType="com.grtsinry43.bookmanagement.entity.Publisher">
+        SELECT * FROM publisher WHERE publisher_id IN
+        <foreach collection="ids" item="id" open="(" separator="," close=")">
+            #{id}
+        </foreach>
+    </select>
+
+    <!-- 5. 查询每个出版社的图书平均价格（连接+GROUP BY+AVG） -->
+    <select id="avgBookPriceByPublisher" resultType="map">
+        SELECT p.name AS publisher_name, AVG(b.price) AS avg_price
+        FROM publisher p
+        JOIN book b ON p.publisher_id = b.publisher_id
+        GROUP BY p.name
+        ORDER BY avg_price DESC
+    </select>
+
 </mapper>

src/main/resources/mapper/ReaderMapper.xml

@@ -27,4 +27,63 @@
         UPDATE reader SET is_banned = #{isBanned} WHERE reader_id = #{readerId}
     </update>
 
+    <!-- 2. 查询每个用户的订单数量（连接+GROUP BY+聚合） -->
+    <select id="findReaderOrderCount" resultType="map">
+        SELECT r.reader_id, r.username, COUNT(o.order_id) AS order_count
+        FROM reader r
+        LEFT JOIN orders o ON r.reader_id = o.reader_id
+        GROUP BY r.reader_id, r.username
+        ORDER BY order_count DESC
+    </select>
+
+    <!-- 3. 查询有订单的用户信息（连接查询） -->
+    <select id="findReadersWithOrders" resultType="com.grtsinry43.bookmanagement.entity.Reader">
+        SELECT DISTINCT r.*
+        FROM reader r
+        JOIN orders o ON r.reader_id = o.reader_id
+    </select>
+
+    <!-- 4. 查询没有下过订单的用户（嵌套NOT IN） -->
+    <select id="findReadersWithoutOrders" resultType="com.grtsinry43.bookmanagement.entity.Reader">
+        SELECT * FROM reader WHERE reader_id NOT IN (SELECT reader_id FROM orders)
+    </select>
+
+    <!-- 5. 查询用户名在指定集合内的用户（IN集合查询） -->
+    <select id="findByUsernames" resultType="com.grtsinry43.bookmanagement.entity.Reader">
+        SELECT * FROM reader WHERE username IN
+        <foreach collection="usernames" item="name" open="(" separator="," close=")">
+            #{name}
+        </foreach>
+    </select>
+
+    <!-- 6. 查询被封禁用户数量（聚合） -->
+    <select id="countBannedReaders" resultType="int">
+        SELECT COUNT(*) FROM reader WHERE is_banned = TRUE
+    </select>
+
+    <!-- 7. 查询有订单且订单金额大于100的用户（嵌套EXISTS+连接） -->
+    <select id="findReadersWithBigOrders" resultType="com.grtsinry43.bookmanagement.entity.Reader">
+        SELECT * FROM reader r WHERE EXISTS (
+            SELECT 1 FROM orders o WHERE o.reader_id = r.reader_id AND o.total_amount > 100
+        )
+    </select>
+
+    <!-- 8. 查询每个用户的最后一次下单时间（连接+GROUP BY+聚合） -->
+    <select id="findLastOrderDateByReader" resultType="map">
+        SELECT r.reader_id, r.username, MAX(o.order_date) AS last_order_date
+        FROM reader r
+        LEFT JOIN orders o ON r.reader_id = o.reader_id
+        GROUP BY r.reader_id, r.username
+    </select>
+
+    <!-- 9. 查询邮箱为某域名的用户（单表LIKE） -->
+    <select id="findByEmailDomain" resultType="com.grtsinry43.bookmanagement.entity.Reader">
+        SELECT * FROM reader WHERE email LIKE CONCAT('%', #{domain})
+    </select>
+
+    <!-- 10. 查询所有未被封禁的管理员（单表多条件） -->
+    <select id="findActiveAdmins" resultType="com.grtsinry43.bookmanagement.entity.Reader">
+        SELECT * FROM reader WHERE is_admin = TRUE AND is_banned = FALSE
+    </select>
+
 </mapper>

src/main/resources/sql/init.sql

@@ -1,5 +1,37 @@
 -- 适用于 PostgreSQL 数据库
 
+-- 触发器：当 book 库存变为 0 时，记录到 out_of_stock_log
+CREATE TABLE IF NOT EXISTS out_of_stock_log (
+    log_id SERIAL PRIMARY KEY,
+    book_id INT NOT NULL,
+    out_time TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE OR REPLACE FUNCTION log_out_of_stock()
+RETURNS TRIGGER AS $$
+BEGIN
+    IF NEW.stock = 0 AND OLD.stock > 0 THEN
+        INSERT INTO out_of_stock_log (book_id) VALUES (NEW.book_id);
+    END IF;
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_book_out_of_stock ON book;
+CREATE TRIGGER trg_book_out_of_stock
+AFTER UPDATE ON book
+FOR EACH ROW
+EXECUTE FUNCTION log_out_of_stock();
+
+-- 存储过程：批量封禁用户
+CREATE OR REPLACE PROCEDURE ban_readers(usernames TEXT[])
+LANGUAGE plpgsql
+AS $$
+BEGIN
+    UPDATE reader SET is_banned = TRUE WHERE username = ANY(usernames);
+END;
+$$;
+
 -- 创建数据库（如需）
 -- CREATE DATABASE book_management;
 
@@ -52,7 +84,7 @@ CREATE TABLE reader
     reader_id SERIAL PRIMARY KEY,
     username  VARCHAR(50)  NOT NULL UNIQUE,
     password  VARCHAR(100) NOT NULL,
-    email     VARCHAR(100) NOT NULL UNIQUE,
+    email     VARCHAR(100) UNIQUE,
     is_admin  BOOLEAN      NOT NULL DEFAULT FALSE,
     is_banned BOOLEAN      NOT NULL DEFAULT FALSE,
     phone     VARCHAR(20)