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Mybatisplus Error querying database.Cause: java.sql.SQLException: Operand should contain 1 column(s)

Mybatis-plus Error querying database. Cause: java.sql.SQLException: Operand should contain 1 column(s)

/*** QueryWrapperSelect 实现子查询*/
@Test
public void QueryWrapperSelectSon(){//查询id小于等于100的用户信息QueryWrapper<User> queryWrapper = new QueryWrapper<>();
//        queryWrapper.inSql("id", "select id from user where id <= 100");queryWrapper.inSql("username", "select * from user where username like '%金%' AND is_deleted=0");List<User> list = userMapper.selectList(queryWrapper);list.forEach(System.out::println);
}

在 Mybatis-Plus 实战项目中 通过 QueryWrapper 构造器实现子查询用户信息的时候报如下错误
Error querying database. Cause: java.sql.SQLException: Operand should contain 1 column(s)

org.springframework.jdbc.BadSqlGrammarException: 
### Error querying database.  Cause: java.sql.SQLException: Operand should contain 1 column(s)
### The error may exist in com/example/mybatisplus/mapper/UserMapper.java (best guess)
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: SELECT  id AS uid,username AS name,age,email,create_time,update_time,is_deleted  FROM user   WHERE  is_deleted=0  AND (id IN (select * from user where id <= 100))
### Cause: java.sql.SQLException: Operand should contain 1 column(s)
; bad SQL grammar []; nested exception is java.sql.SQLException: Operand should contain 1 column(s)

报错原因：
select * from user where username like ‘%金%’ AND is_deleted=0 不能为 * ，而必须是数据库表中的某个字段才行

解决方法： 将 * 换成表中具体字段名，比如：username或id等等，即可解决报错问题


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本文标签： Mybatisplus Error querying databaseCause javasqlSQLException Operand should contain 1 column(s)

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