Mybatis的@Param注解的作用,我个人感觉就俩作用:1.便于传多个参数;2.类似于别名之类的功能
- 1
1.便于传多个参数
dao层示例:
Public User selectUser(@param(“userName”) String name,
@param(“userpassword”) String password);
对应的mapper.xml
select * from user_user_t where user_name = #{userName} and user_password=#{userPassword}
不使用@Param注解时,参数只能有一个,而且是JavaBean,在sql中只能引用JavaBean的属性。
2.类似于别名之类的功能
数据库中字段为:user_name、user_password;
pojo类中字段为:name、password;
传参时别名字段为:userName,userPassword
本人才疏学浅,写这些是便于自己记住,有不足的地方请大佬指正,谢谢。
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Mybatis的@Param注解的作用,我个人感觉就俩作用:1.便于传多个参数;2.类似于别名之类的功能
- 1
1.便于传多个参数
dao层示例:
Public User selectUser(@param(“userName”) String name,
@param(“userpassword”) String password);
对应的mapper.xml
select * from user_user_t where user_name = #{userName} and user_password=#{userPassword}
不使用@Param注解时,参数只能有一个,而且是JavaBean,在sql中只能引用JavaBean的属性。
2.类似于别名之类的功能
数据库中字段为:user_name、user_password;
pojo类中字段为:name、password;
传参时别名字段为:userName,userPassword
本人才疏学浅,写这些是便于自己记住,有不足的地方请大佬指正,谢谢。
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作者:别抢我蓝buff
链接:https://blog.csdn.net/qq_44813090/article/details/104141535