MyBatis动态 SQL语法多条件 AND/OR 语句代码示例

<select id="findUser" resultType="User">
   select * from users 
   <where>
     <choose>
       <when test="id != null">
         and id = #{id}   
       </when>   
       <when test="email != null">
         and email = #{email}        
       </when>   
       <otherwise>
         and username = #{username}       
       </otherwise>   
     </choose>    
   </where>
</select>