解决一个mybatisplus left join里有ur报错问题

今天调试没有注意写了下面语句

select
	   		sns.send_id,
	   		sns.notice_id,
	   		sns.user_id,
	   		sns.read_flag,
	   		sa.notice_title as notice_title,
	   		sa.notice_content as notice_content,
	   		sa.sender as sender,
	   		sa.priority as priority,
	   		sa.notice_type as notice_type,
	   		sa.send_time as send_time
	   from sys_notice_send sns
	   left join sys_notice sa ON sns.notice_id = sa.notice_id
	   left join sys_user ur ON sns.user_id = ur.user_id
	   where sa.send_status = '1'
	   and sa.status = '0'
	   and sns.user_id = #{noticeSendModel.userId}

结果报错，如下：

at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:427)
	... 109 common frames omitted
Caused by: com.baomidou.mybatisplus.core.exceptions.MybatisPlusException: Failed to process, Error SQL: select
	   		sns.send_id,
	   		sns.notice_id,
	   		sns.user_id,
	   		sns.read_flag,
	   		sa.notice_title as notice_title,
	   		sa.notice_content as notice_content,
	   		sa.sender as sender,
	   		sa.priority as priority,
	   		sa.notice_type as notice_type,
	   		sa.send_time as send_time
	   from sys_notice_send sns
	   left join sys_notice sa ON sns.notice_id = sa.notice_id
	   left join sys_user ur ON sns.user_id = ur.user_id
	   where sa.send_status = '1'
	   and sa.status = '0'
	   and sns.user_id = ?
	    
	    
	    
         
	   order by sns.read_flag,sa.send_time desc
	at com.baomidou.mybatisplus.core.toolkit.ExceptionUtils.mpe(ExceptionUtils.java:39)
	at com.baomidou.mybatisplus.extension.parser.JsqlParserSupport.parserSingle(JsqlParserSupport.java:52)
	at com.ruoyi.framework.interceptor.PlusDataPermissionInterceptor.beforeQuery(PlusDataPermissionInterceptor.java:49)
	at com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor.intercept(MybatisPlusInterceptor.java:78)
	at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:62)
	at com.sun.proxy.$Proxy251.query(Unknown Source)
	at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:151)
	... 116 common frames omitted
Caused by: net.sf.jsqlparser.parser.ParseException: Encountered unexpected token: "ur" 
    at line 14, column 24.

开始没有注意，以为是sql语句有问题，后来在navicat里执行好像也没有错误。

后来再仔细看后，发现说ur是关键字？不能用ur，果然用下面语句就好了。

select
	   		sns.send_id,
	   		sns.notice_id,
	   		sns.user_id,
	   		sns.read_flag,
	   		sa.notice_title as notice_title,
	   		sa.notice_content as notice_content,
	   		u.nick_name as sender,
	   		sa.priority as priority,
	   		sa.notice_type as notice_type,
	   		sa.send_time as send_time
	   from sys_notice_send sns
	   left join sys_notice sa ON sns.notice_id = sa.notice_id
       left join sys_user u ON sns.user_id = u.user_id
	   where sa.send_status = '1'
	   and sa.status = '0'
	   and sns.user_id = #{noticeSendModel.userId}

注意出错日志里有这句Caused by: net.sf.jsqlparser.parser.ParseException: Encountered unexpected token: "ur"

说明是跟ur相关了。