NHibernate HQL是否支持UNION ALL关键字? [英] Does NHibernate HQL support the UNION ALL keyword?

问题描述

经过广泛的谷歌搜索，我仍然找不到这个问题的明确答案.我见过的一些旧文章/博客文章根本没有说.如果基础数据库支持，则有人说是.哪有到目前为止，我没有回答nhusers组.任何帮助将不胜感激.

After extensive googling, I still can't find a definitive answer to this question. Some old articles/blog posts I've seen say not at all. Some say yes if the underling database supports it. Which is it? I asked on the nhusers group with no answer so far. Any help would be appreciated.

推荐答案

NHibernate不支持联合.结果始终只有一种类型.

NHibernate does not support union. There is always one type in a result.

您可以做的是查询基类或接口. NHibernate将执行并集以从实体所映射到的所有表中获取所有值.

What you can do is a query to a base class or interface. NHibernate will perform a union to get all the values from all tables where the entities are mapped to.

还有union-subclass映射策略，这也意味着存在基类或接口.

There is also the union-subclass mapping strategy, which also implies that there is a base class or interface.

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