项目场景：

提示：这里简述项目相关背景：
mybatis查询数据

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问题描述：

提示：这里描述项目中遇到的问题：

org.apache.ibatis.exceptions.PersistenceException:

Error querying database. Cause: java.sql.SQLSyntaxErrorException: Table ‘jt.demouser’ doesn’t exist

The error may exist in mybatis/mappers/DemoUserMapper.xml

The error may involve defaultParameterMap

The error occurred while setting parameters

SQL: select * from DemoUser

Cause: java.sql.SQLSyntaxErrorException: Table ‘jt.demouser’ doesn’t exist

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原因分析：

提示：xml配置文件SQL语句的表名和数据库的不一样

<mapper namespace="com.jt.mappers.DemoUserMapper">
<select id="findAll" resultType="com.jt.pojo.DemoUser">
select * from DemoUser
</select>
</mapper>

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解决方案：

提示：修改xml SQL语句的表名

<mapper namespace="com.jt.mappers.DemoUserMapper">
<select id="findAll" resultType="com.jt.pojo.DemoUser">
/*select * from DemoUser*/
--修改后
select * from demo_user
</select>
</mapper>