功能NHibernate - 选择特定的列和数量的查询与GROUP BY [英] Fluent Nhibernate - selecting specific column and count query with group by
问题描述
我有一些麻烦excuting用流利的NHibernate的查询。
我有一个表:书籍有以下栏目:
ID,名称,年份,BOOK_TYPE,AUTHOR_ID
我要EXCUTE在功能NHibernate下面的SQL查询:
SELECT BOOK_TYPE,COUNT(*)
从书本
GROUP BY BOOK_TYPE
所谓的流利,NHibernate的的仅仅是一个映射扩展。为了获取数据,我们需要NHibernate的内置ñ查询功能:的ICriteria
, QueryOver
甚至 LINQ 。
根据文档上我们可以使用预测对于上述情况下,使用 QueryOver
API
16.6。 QueryOver - 预测
中的代码片段:
IList的选择=
session.QueryOver<图书>()
.SelectList(名单=>清单
。选择(C => c.BooktType)
.SelectCount(C = GT; c.ID))
&的.List LT;对象[]>();
I'm having some trouble excuting a query in fluent nhibernate. I have a table : Books with the following columns:
ID, NAME, YEAR, BOOK_TYPE, AUTHOR_ID
I want to excute the following sql query in Fluent NHibernate:
SELECT BOOK_TYPE, COUNT(*)
FROM BOOKS
GROUP BY BOOK_TYPE
So called Fluent-NHibernate is just a mapping extension. To get data we need NHibernate built n querying features: ICriteria
, QueryOver
or even a LINQ.
Based on the documentation we can use projections for the above case, using the QueryOver
API
16.6. QueryOver - Projections
The code snippet:
IList selection =
session.QueryOver<Book>()
.SelectList(list => list
.Select(c => c.BooktType)
.SelectCount(c => c.ID))
.List<object[]>();
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