<select id="getFselection" parameterType="java.lang.String" resultType="com.college.collegesystem.pojo.DO.CollegeScoreFselectionSheet"> SELECT username, provinceId, referenceYear, batch, subject, score FROM college_score_fselection_sheet where username = #{username} and province_id = #{provinceId} and reference_year = #{referenceYear} and batch = #{batch} and subject = #{subject} and score = #{score}这段代码应怎样修改正确
时间: 2024-03-16 16:46:06 浏览: 50
这段代码中的SQL语句似乎没有问题,但是参数#{provinceId}的类型需要指定为Integer或者其他对应的JdbcType,因为在SQL语句中没有指定JdbcType,所以MyBatis无法自动判断参数类型。可以在参数类型前面加上"@Param"注解,并指定JdbcType,如下所示:
```
<select id="getFselection" parameterType="java.lang.String" resultType="com.college.collegesystem.pojo.DO.CollegeScoreFselectionSheet">
SELECT username, provinceId, referenceYear, batch, subject, score
FROM college_score_fselection_sheet
where username = #{username} and province_id = #{provinceId,jdbcType=INTEGER} and reference_year = #{referenceYear} and batch = #{batch} and subject = #{subject} and score = #{score}
</select>
```
这样就可以解决类型转换错误的问题。
相关问题
<select id="getFselection" parameterType="java.lang.String" resultType="com.college.collegesystem.pojo.DO.CollegeScoreFselectionSheet"> SELECT username, provinceId, referenceYear, batch, subject, score FROM college_score_fselection_sheet where username = #{username} and province_id = #{provinceId} and reference_year = #{referenceYear} and batch = #{batch} and subject = #{subject} and score = #{score} </select>怎样改正确
根据错误信息,参数`provinceId`的类型为`String`,但是在设置参数时出现了类型转换异常,尝试将一个`Integer`类型的值强制转换为`String`类型。因此,建议将该SQL语句中的`provinceId`参数的类型改为`Integer`,并且在调用该SQL语句时,传入的参数也应该是`Integer`类型的。
修改后的SQL语句如下所示:
```
<select id="getFselection" parameterType="com.college.collegesystem.pojo.DO.CollegeScoreFselectionSheet" resultType="com.college.collegesystem.pojo.DO.CollegeScoreFselectionSheet">
SELECT username, provinceId, referenceYear, batch, subject, score
FROM college_score_fselection_sheet
WHERE username = #{username}
AND provinceId = #{provinceId}
AND referenceYear = #{referenceYear}
AND batch = #{batch}
AND subject = #{subject}
AND score = #{score}
</select>
```
同时,在调用该SQL语句时,传入的参数`provinceId`应该是`Integer`类型的。
<?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 namespace="com.phonemarket.mapper.BannerMapper"> <resultMap type="Banner" id="BaseResultMap"> <id property="bannerId" column="banner_id" /> <result property="bannerName" column="banner_name" /> <result property="bannerUrl" column="banner_url" /> <result property="bannerImg" column="banner_img" /> <result property="bannerState" column="banner_state" /> </resultMap> <insert id="addBanner" parameterType="Banner"> insert into banner(banner_name,banner_url,banner_img) values(#{bannerName},#{bannerUrl},#{bannerImg}) </insert> <update id="deleteBanner" parameterType="java.lang.Integer"> update banner set banner_state=-1 where banner_id=#{id} </update> <update id="changeBannerState" parameterType="java.lang.Integer"> update banner set banner_state=#{0} where banner_id=#{1} </update> <update id="updateBanner" parameterType="Banner"> update banner <set> <if test="bannerName!=null"> banner_name=#{bannerName}, </if> <if test="bannerUrl!=null"> banner_url=#{bannerUrl}, </if> <if test="bannerImg!=null"> banner_img=#{bannerImg} </if> </set> where banner_id=#{bannerId} </update> <select id="findBannerById" parameterType="java.lang.Integer" resultMap="BaseResultMap"> select * from banner where banner_id=#{id} </select> <select id="findAllBanner" resultMap="BaseResultMap"> select * from banner where banner_state > 0 </select> <select id="findAllBannerByLikeName" parameterType="java.lang.String" resultMap="BaseResultMap"> select * from banner where banner_state > 0 and banner_name like '%${value}%' </select> <select id="findAllShowBanner" resultMap="BaseResultMap"> select * from banner where banner_state=1 </select> </mapper>
这是一个 MyBatis 的 XML 配置文件,用于映射 Banner 对象和 banner 数据库表之间的关系。文件中定义了一个 namespace 为 com.phonemarket.mapper.BannerMapper 的 Mapper,并包含了一些 SQL 语句,如插入、删除、更新和查询等。括号中的参数类型表示 SQL 语句中的参数类型,resultMap 定义了查询结果与 Banner 对象之间的映射关系。其中BaseResultMap是一个标识符,表示基本的结果映射,对应了Banner类中的属性名称。在 SQL 语句中,#{param} 表示参数占位符,${value} 表示变量占位符。
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