在Nhibernate中创建查询"sum“多个列

using NHibernate;
using NHibernate.Criterion;

// 创建一个投影列表
var projectionList = Projections.ProjectionList();

// 添加需要查询的列和对应的总和计算
projectionList.Add(Projections.Sum(Projections.Property("Column1")), "SumColumn1");
projectionList.Add(Projections.Sum(Projections.Property("Column2")), "SumColumn2");
projectionList.Add(Projections.Sum(Projections.Property("Column3")), "SumColumn3");

// 创建查询
var query = session.CreateCriteria<YourEntity>()
    .SetProjection(projectionList)
    .UniqueResult<object[]>();

// 获取查询结果
var sumColumn1 = (int)query[0];
var sumColumn2 = (int)query[1];
var sumColumn3 = (int)query[2];