选择标准只有几列 [英] selecting only few columns with criteria

问题描述

 从ioa_book选择aaa，bbb，ccc，ddd 
  

如图所示，它正在击打表ioa_book并且只选择了几列，相应的pojo名称是boop ..现在我想将它转换为休眠标准，但它加载了所有不需要的列，我仍然想使用标准并选择列本身，请告知如何实现此目的。

所以我就这样走了......

  Criteria criteria = session.createCriteria（boop。类）; 
列表< boop> books = criteria.list（）; 
  

请指教

解决方案

  criteria.setProjection（
 Projections.projectionList（）
 .add（Projections.property（aaa））
 .add （Projections.property（bbb））
 .add（Projections.property（ccc））
）; 
 List< Object []> result = criteria.list（）; 
  

这是有文档记录。

I have the database query such as ,..

select aaa, bbb, ccc, ddd from ioa_book

as shown it is hitting the table ioa_book and only selecting few columns , the corresponding pojo name is boop .. and now I want to convert it into criteria of hibernate one but it loads all the columns that i do not want , i still want to use criteria and with selected columns itself , please advise how to achieve this..

so I have gone by this way...

 Criteria criteria = session.createCriteria(boop.class);
 List<boop> books = criteria.list();

please advise

解决方案

criteria.setProjection(
    Projections.projectionList()
        .add(Projections.property("aaa"))
        .add(Projections.property("bbb"))
        .add(Projections.property("ccc")) 
    );
List<Object[]> result = criteria.list();

This is documented.

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