错误信息

</details>org.springframework.security.authentication.InternalAuthenticationServiceException: Invalid bound statement (not found): com.why.security.mapper.UsersMapper.selectOne
	at org.springframework.security.authentication.dao.DaoAuthenticationProvider.retrieveUser(DaoAuthenticationProvider.java:108) ~[spring-security-core-5.4.9.jar:5.4.9]
	at org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider.authenticate(AbstractUserDetailsAuthenticationProvider.java:133) ~[spring-security-core-5.4.9.jar:5.4.9]
	at org.springframework.security.authentication.ProviderManager.authenticate(ProviderManager.java:182) ~[spring-security-core-5.4.9.jar:5.4.9]
	at org.springframework.security.authentication.ProviderManager.authenticate(ProviderManager.java:201) ~[spring-security-core-5.4.9.jar:5.4.9]
	at org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter.attemptAuthentication(UsernamePasswordAuthenticationFilter.java:85) ~[spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:222) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:212) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:103) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:89) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.csrf.CsrfFilter.doFilterInternal(CsrfFilter.java:132) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.3.12.jar:5.3.12]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:90) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:75) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.3.12.jar:5.3.12]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:110) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:80) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:55) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.3.12.jar:5.3.12]
	at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:211) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:183) [spring-security-web-5.4.9.jar:5.4.9]
	at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:358) [spring-web-5.3.12.jar:5.3.12]
	at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:271) [spring-web-5.3.12.jar:5.3.12]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) [spring-web-5.3.12.jar:5.3.12]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.3.12.jar:5.3.12]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) [spring-web-5.3.12.jar:5.3.12]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.3.12.jar:5.3.12]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) [spring-web-5.3.12.jar:5.3.12]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.3.12.jar:5.3.12]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:540) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:357) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:382) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:895) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1722) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.54.jar:9.0.54]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_251]
Caused by: org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.why.security.mapper.UsersMapper.selectOne
	at org.apache.ibatis.binding.MapperMethod$SqlCommand.<init>(MapperMethod.java:214) ~[mybatis-3.4.0.jar:3.4.0]
	at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:48) ~[mybatis-3.4.0.jar:3.4.0]
	at org.apache.ibatis.binding.MapperProxy.cachedMapperMethod(MapperProxy.java:59) ~[mybatis-3.4.0.jar:3.4.0]
	at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:52) ~[mybatis-3.4.0.jar:3.4.0]
	at com.sun.proxy.$Proxy59.selectOne(Unknown Source) ~[na:na]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_251]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_251]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_251]
	at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_251]
	at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:344) ~[spring-aop-5.3.12.jar:5.3.12]
	at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:198) ~[spring-aop-5.3.12.jar:5.3.12]
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.3.12.jar:5.3.12]
	at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137) ~[spring-tx-5.3.12.jar:5.3.12]
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.12.jar:5.3.12]
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:215) ~[spring-aop-5.3.12.jar:5.3.12]
	at com.sun.proxy.$Proxy60.selectOne(Unknown Source) ~[na:na]
	at com.why.security.service.MyUserService.loadUserByUsername(MyUserService.java:39) ~[classes/:na]
	at org.springframework.security.authentication.dao.DaoAuthenticationProvider.retrieveUser(DaoAuthenticationProvider.java:93) ~[spring-security-core-5.4.9.jar:5.4.9]
	... 57 common frames omitted

解决方法

1、首先检查Springboot启动类的@MapperScan()注解

我的springboot启动类如下

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@MapperScan(basePackages = "com.why.security.mapper")
@SpringBootApplication
public class SpringSecurityApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringSecurityApplication.class, args);
    }

}

2、重启还是报错，检查引入依赖。

问题：按照官网说springboot的普通项目只需要引入我一开始引入的jar包就可以，但是我引入之后还是报错。

1、我一开始的引入

<dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus</artifactId>
            <version>3.0.2</version>
</dependency>

2、我解决引入的依赖

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.1.2</version>
</dependency>
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-annotation</artifactId>
    <version>3.1.2</version>
</dependency>
<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-extension</artifactId>
    <version>3.1.2</version>
</dependency>

遇见其他问题官网已经写的很清楚了！
附链接：https://mp.baomidou.com/guide/faq.html