mysql关键字引发错误：org.springframework.jdbc.BadSqlGrammarException

🎈1 参考文档

mysql关键字简介（附简单使用说明） | 荒野漫步者-优快云

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🔍2 问题描述

org.springframework.jdbc.BadSqlGrammarException: 
### Error querying database.  Cause: java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'leave WHERE is_delete = 0' at line 1
### The error may exist in com/hyc/nsms/mapper/LeaveMapper.java (best guess)
### The error may involve defaultParameterMap
### The error occurred while setting parameters
### SQL: SELECT COUNT(*) AS total FROM leave WHERE is_delete = 0
### Cause: java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'leave WHERE is_delete = 0' at line 1;
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💡3 排错思路

3.1 xml问题

1. 一开始看到日志的这句：### The error may exist in com/hyc/nsms/mapper/LeaveMapper.java (best guess)。查看mapper层的文件，但我使用的是mybatis-plus，mapper层里面根本没有写任何内容。
2. 以为是target里面没有生成xml文件。查看target之后发现生成了xml文件，即使重新打包后，还是出现同样的错误。
3. 百度了很多关于xml相关的问题，发现都没有用。

3.2 sql语句错误

1. 根据日志这句：check the manual that corresponds to your MySQL server version for the right syntax to use near 'leave WHERE is_delete = 0' at line 1。

2. 输入SELECT COUNT(*) AS total FROM leave WHERE is_delete = 0查询,发现报错。

   

3. 输入SELECT COUNT(*) AS total FROM leave WHERE is_delete = 0查询,发现查询成功。

   

4. 最后发现问题：粗心大意，字段不能是MySQL关键字。

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🚀四、解决方案

1. 将表名leave改成其他，如：ask_for_leave。
2. 查看其他MySQL关键字，避免错误。