ibatis select标签

ibatis select 标签详解

select的输入和输出

例如 select id,name,age from user where name like '%王%' and age>20

这里既有输入也有输出

select的属性
id,parameterClass,resultClass,parameterMap,resultMap,cacheModel
resultSetType,fetchSize,xmlResultName,remapResults,timeout
输入 parameterClass,ParameterMap
resultSetTYpe为结果集类型，主要是说游标，具有方向性，可以取
forward_only,scoll_insensitive,scoll_sensitive,具体情况具体配置

fetchSize 预取回数据量的大小

xmlResultName,返回result为xml的名称

如果返回的结果可以修改则吧remapResults设为true,否则设为false

输入，用参数带进来
可以是#，$做为占位符

不同占位符使用

<select id="getAllUsers1" resultClass="com.mypackage.User"
  parameterClass="string">
  SELECT * FROM USER WHERE DEPARTMENT=#department#
 </select>
<select id="getAllUsers1" resultClass="com.mypackage.User"
  parameterClass="string">
  SELECT * FROM USER WHERE DEPARTMENT like '$department$'
 </select>

 

#不能放在‘’之内

resultMap

 

<!-- 无映射  -->
 <select id="getAllUsers1" resultClass="User"
  parameterClass="string">
  SELECT * FROM USER WHERE DEPARTMENT=#department#
 </select>

 <!-- 内联映射->实体类 -->
 <select id="getAllUsers2" resultClass="User"
  parameterClass="string">
  SELECT USERID as userid, USERNAME as username, PASSWORD as
  password, DEPARTMENT as department FROM USER WHERE
  DEPARTMENT=#department#
 </select>

 <!-- 内联映射->MAP类 -->
 <select id="getAllUsers3" resultClass="hashmap"
  parameterClass="string">
  SELECT * FROM USER WHERE DEPARTMENT=#department#
 </select>

 <!-- 显示映射->实体类 -->
 <resultMap id="accoutResult" class="User">
  <result property="userid" column="USERID" />
  <result property="username" column="USERNAME" />
  <result property="password" column="PASSWORD" />
  <result property="department" column="DEPARTMENT" />
 </resultMap>
 <select id="getAllUsers4" resultMap="accoutResult"
  parameterClass="string">
  SELECT * FROM USER WHERE DEPARTMENT=#department#
 </select>

 <!-- 显示映射->MAP类 -->
 <resultMap id="mapResult" class="hashmap">
  <result property="userid" column="USERID" />
  <result property="username" column="USERNAME" />
  <result property="password" column="PASSWORD" />
  <result property="department" column="DEPARTMENT" />
 </resultMap>
 <select id="getAllUsers5" resultMap="mapResult"
  parameterClass="string">
  SELECT * FROM USER WHERE DEPARTMENT=#department#
 </select>

 

 map映射 ，返回的list里的每一项都是一个map然后有键值对

xml映射

<!-- XML -->
 <select id="selectXML" parameterClass="string" resultClass="xml"
  xmlResultName="log">
  SELECT * FROM USER_ACCOUNT WHERE GROUPNAME=#groupName#
 </select>

  

resultClass="xml"这个xml也是预定义好的类

在测试类里调用后返回的是xml格式的字符串，指定的xmlResultName相当于xml的
根元素

 

返回结果有三类，1 返回直接指定的类 2 返回map类型 3 返回xml