关于MyBaties的基本配置标签总结

<properties resource="dbconfig.properties"></properties>

<settings>
   <setting name="mapUnderscoreToCamelCase" value="true"/>
</settings>

<typeAlias type="com.atguigu.mybatis.bean.Employee" alias="emp"/> 

<package name="com.atguigu.mybatis.bean"/>

@Alias("emp")
public class Employee {
    ...code...
}

<environments default="dev_mysql">
   <environment id="dev_mysql">
      <transactionManager type="JDBC"></transactionManager>
      <dataSource type="POOLED">
         <property name="driver" value="${jdbc.driver}" />
         <property name="url" value="${jdbc.url}" />
         <property name="username" value="${jdbc.username}" />
         <property name="password" value="${jdbc.password}" />
      </dataSource>
   </environment>

   <environment id="dev_oracle">
      <transactionManager type="JDBC" />
      <dataSource type="POOLED">
         <property name="driver" value="${orcl.driver}" />
         <property name="url" value="${orcl.url}" />
         <property name="username" value="${orcl.username}" />
         <property name="password" value="${orcl.password}" />
      </dataSource>
   </environment>
</environments>

<databaseIdProvider type="DB_VENDOR">
   <!-- 为不同的数据库厂商起别名 -->
   <property name="MySQL" value="mysql"/>
   <property name="Oracle" value="oracle"/>
   <property name="SQL Server" value="sqlserver"/>
</databaseIdProvider>

<mapper namespace="com.atguigu.mybatis.dao.EmployeeMapper">
	<select id="getEmpById" resultType="com.atguigu.mybatis.bean.Employee">
       select * from tbl_employee where id = #{id}
    </select>
    <select id="getEmpById" resultType="com.atguigu.mybatis.bean.Employee"
       databaseId="mysql">
       select * from tbl_employee where id = #{id}
    </select>
    <select id="getEmpById" resultType="com.atguigu.mybatis.bean.Employee"
       databaseId="oracle">
       select EMPLOYEE_ID id,LAST_NAME    lastName,EMAIL email 
       from employees where EMPLOYEE_ID=#{id}
    </select>
</mapper>

<mapper resource="mybatis/mapper/EmployeeMapper.xml"/>

public interface EmployeeMapperAnnotation {
	@Select("select * from tbl_employee where id=#{id}")
	public Employee getEmpById(Integer id);
}

<mapper class="com.atguigu.mybatis.dao.EmployeeMapperAnnotation"/>

<package name="com.atguigu.mybatis.dao"/>