Exception in thread "main" redis.clients.jedis.exceptions.JedisDataException 1.进入redis的src目录下 输入：./redis-cli将受保护模式选项设置为“no”，为了让服务器开始从外部接受连接输入：config set protected-mode "no"

ssm不执行sql，不报错且程序接着运行 org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.builder.BuilderException: Error evaluating expression 'programa.pId != null'. Cause: org.apache.ibatis.ognl.OgnlException: source is null for getProperty(null, "pId")------------------------------------------------------SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@68a32861] was not registered for synchronization because synchronization is not active------------------------------------------------------Caused by: org.apache.ibatis.builder.BuilderException: Error evaluating expression 'programa.pId != null'. Cause: org.apache.ibatis.ognl.OgnlException: source is null for getProperty(null, "pId")  最开始删除的方法没有try不知道错在哪里也没抛异常 动态拼接的时候最开始用的只是根据programa.pId做条件删除，所有本身Article对象的aId属性是为空的，删除的时候没有问题。<if test="aId != null ">and a_id=#{aId} </if> <if test="programa.pId != null" > and p_id=#{programa.pId} </if>当我根据aId来删除的时候，条件还是↓↓↓↓<if test="aId != null ">and a_id=#{aId} </if> <if test="programa.pId != null" > and p_id=#{programa.pId} </if>到这里的时候就怎么也不执行删除的sql，代码还是接着运行，发现是因为没有判断对象属性不为空一次泪奔的总结┭┮﹏┭┮

org.springframework.data.redis.RedisConnectionFailureException: Cannot get Jedis connection; nested redis连接报错Type Exception ReportMessage Request processing failed; nested exception is org.springframework.data.redis.RedisConnectionFailureException: Cannot get Jedis connection; nested exception is redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the poolDescription The server encountered an unexpected condition that prevented it from fulfilling the request. 进入Linux，修改redis配置  config set protected-mode "no"

Caused by: java.net.ConnectException: Connection timed out: connect spring boot项目整合mybatis时连接数据库报错Caused by: java.net.ConnectException: Connection timed out: connect我的是因为linux上的防火墙及3306端口没开放参考：https://blog.csdn.net/qq_40369944/article/details/85007397 

Navicat Premium 12连接SQL Server时出错：未发现数据源名称并且未指定默认驱动程序 下载sqlncli.msi 并安装：下载新建SQL Server --> 选择高级，按照下面的方式选择我的安装路径在：C:\Program Files\Microsoft SQL Server\110点击“测试连接”，可以看到连接成功了

feign.FeignException: status 404 reading GoodsServiceClient#goodsInfo(String) 有可能是 ‘消费者’ 调用 ‘服务提供者’ 的时候路径错误或者参数少了

org.apache.coyote.http11.Http11Processor.service Error parsing HTTP request header tomcat 能访问界面，但是程序接口一直没有响应。修改server.xml，添加 maxHttpHeaderSize="81920" <Connector port="8989" protocol="HTTP/1.1" maxHttpHeaderSize="81920" connectionTimeout="20000" redirectPort="8443" />重启tomcat测试发现没有问题

ERROR: '对实体 "web_id" 的引用必须以 ';' 分隔符结尾。' 加载界面提示：ERROR:  '对实体 "web_id" 的引用必须以 ';' 分隔符结尾。'解决方式：在变量前加上“amp;”即可。错误示例：<script src="https://****.com?id=1277655852&web_id=1277655852" language="JavaScript"></script>修改后：<script src="https://****.com?id=1277655852&amp;web_id=1277655852" language="JavaScript"></script> 

UnableToRegisterMBeanException: Unable to register MBean [org.springframework.cloud.context.environm 解决方法：在配置文件中添加以下配置spring: jmx: enabled: false  

Exception in thread "main" java.lang.AbstractMethodError: org.springframework.boot.context.config.Co Exception in thread "main" java.lang.AbstractMethodError: org.springframework.boot.context.config.ConfigFileApplicationListener.supportsSourceType(Ljava/lang/Class;)Z依赖冲突：spring boot使用以下版本，之前使用的是<version>2.1.3.RELEASE</version> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent>