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MyBatis ??? SQL ????

??MyBatis ??????

MyBatis ???????? mybatis-config.xml?????????????? SQL ???????????????

1. ??????

properties ?????????????? mydata.properties???????? src/main/resources ??????????????? ${} ???????????

2. ???????

environments ????????????default ???????????? development???????????

• transactionManager?????????????? JDBC?
• dataSource???????????? UNPOOLED?POOLED ? JNDI ?????

3. SQL ??????

mappers ???? SQL ??????????????????????

• ?????? resource="PersonMapper.xml"?
• ?????? <package name="com.example.mapper"/>?
• ??????? <mapper class="com.example.mapper.PersonMapper"/>?
• ???????? url="file:///??/PersonMapper.xml"?

??SQL ????

SQL ?????? PersonMapper.xml?????????????? SQL ??????????

     
    
         insert into t_person values (null, #{pername}, #{perage}, #{peraddress});  
      
    
         update t_person set per_name=#{pername}, per_age=#{perage}, per_address=#{peraddress} where per_id=#{perid};  
      
    
         delete from t_person where per_id=#{perid};  
      
        select * from t_person where per_id=#{perid};    
        
         
         
         
       
    
   

1. namespaces

namespace ???????????????????

2. SQL ??

• insert???????parameterType ???????
• update??????parameterType ???????
• delete??????parameterType ???????
• select??????parameterType ???????resultMap ???????

3. resultMap

resultMap ????????????????????id ?????????result ?????????

????????

?????????????????????????????