用于书写SQL语句的Mapper.xml文件

文章目录

• 一、图片浏览
• 二、bookMapper.xml文件代码

一、图片浏览

二、bookMapper.xml文件代码

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!-- mapper标签下的路径是dao层的路径，因为dao层原本是用于书写SQL语句的 -->
<mapper namespace="com.demo.ssm.dao.BookDao">
    <select id="search" resultType="book">
        select * from book
        <where>
            <if test="bookName != null and bookName != '' ">
                and bname = #{bookName}
            </if>
            <if test="bookAuthor != null and bookAuthor != '' ">
                and author = #{bookAuthor}
            </if>
            <if test="lowPrice != null and lowPrice != '' ">
                and price >= #{lowPrice}
            </if>
            <if test="highPrice != null and highPrice != '' ">
                and price <= #{highPrice}
            </if>
        </where>
    </select>
</mapper>