1. 在页面输入内容进行搜索时，报错FUNCTION login.CONCAT does not exist
四月 10, 2018 2:39:49 下午 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet [springmvc] in context with path [/SpringDemo] threw exception [Request processing failed; nested exception is org.springframework.jdbc.BadSqlGrammarException: ### Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: FUNCTION login.CONCAT does not exist ### The error may exist in com/game/mapper/NoticesMapper.java (best guess) ### The error may involve com.game.mapper.NoticesMapper.count-Inline ### The error occurred while setting parameters ### SQL: SELECT count(*) FROM notices WHERE ( noticeName LIKE CONCAT ('%',?,'%') ) ### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: FUNCTION login.CONCAT does not exist ; bad SQL grammar []; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: FUNCTION login.CONCAT does not exist] with root cause com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: FUNCTION login.CONCAT does not exist
原因：函数和括号之间不能有空格
SELECT * FROM Notices WHERE noticeContent LIKE CONCAT('%',#{notice.noticeContent},'%')
2.根据id删除数据时，报错：Unknown column 'id' in 'where clause'
四月 10, 2018 3:59:22 下午 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet [springmvc] in context with path [/SpringDemo] threw exception [Request processing failed; nested exception is org.springframework.jdbc.BadSqlGrammarException: ### Error updating database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'id' in 'where clause' ### The error may involve com.game.mapper.NoticesMapper.deleteById-Inline ### The error occurred while setting parameters ### SQL: delete from notices where id = ? ### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'id' in 'where clause' ; bad SQL grammar []; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'id' in 'where clause'] with root cause com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'id' in 'where clause'
原因：SQL语句中的字段与数据库中的字段不对应
//根据id删除公告 @Delete(" delete from notices where id = #{id} ")//数据库中的字段是noticeID，而这里写成了id void deleteById(@Param("id") Integer id);
3. 想起来一个之前没用框架时因为SQL语句空格问题导致的错误，写一块吧
报错：mysql：Not unique table/alias: 'student'
原因：eclipse中的SQL语句在换行时，少了一个空格。
