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  • 最近用到mysql和mybatis结合常用的知识点坐下整理

    1、当用到集合in(x,x...)参数可以单个或者多个 ,当为单个时:

    findbyIds(List<Long> ids),或者findByids(Long [] ids)

     <select id="findByIdsMap" resultMap="BaseResultMap">

         Select
             <include refid="Base_Column_List" />
             from jria where ID in
                     <foreach item="item" index="index" collection="list"
                            open="(" separator="," close=")">
                           #{item}
                   </foreach>

     </select>

    当为数组时 collection="array"

    当查询的参数有多个时,例如 findByIds(String name, Long[] ids)

    这种情况需要特别注意,在传参数时,一定要改用Map方式, 这样在collection属性可以指定名称
             下面是一个示例
             Map<String, Object> params = new HashMap<String, Object>(2);
            params.put("name", name);
             params.put("ids", ids);
            mapper.findByIdsMap(params);
     <select id="findByIdsMap" resultMap="BaseResultMap">
                    select
                    <include refid="Base_Column_List" />
             from jria where ID in
                     <foreach item="item" index="index" collection="ids"
                            open="(" separator="," close=")">
                           #{item}
                   </foreach>

      </select>
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  • 原文地址:https://www.cnblogs.com/likun10579/p/5809581.html
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