Entity framework 平均值,按查询分组
Entity framework average , group by query
您好,我有以下问题
var myList = (from p in db.Full
where (p.date_reception > begin & p.date_reception < end & !p.mc_object.Contains("NULL")
& (!strListe.Contains(p.mc_object)))
group p by new { p.mc_object} into g
select g.OrderByDescending(p => new {p.duration,p.mc_object} ) into r
select new StringIntType
{
str = r.mc_object,
nbr = r.duration.Value
}).Take(50).ToList();
我需要按 mc_object 和 select mc_object 分组,平均持续时间
并按平均持续时间降序排列,感谢您的帮助
查询应该是
var myList = (from p in db.Full
// Don't use &! Use &&
where p.date_reception > begin &&
p.date_reception < end &&
!p.mc_object.Contains("NULL") &&
!strListe.Contains(p.mc_object)
group p by p.mc_object into g
select new
{
mc_object = g.Key,
/* data = g, */
avg = g.Average(x => x.duration)
} into h
// if you want both descending, add descending after mc_object
orderby h.avg descending, h.mc_object
select new StringIntType
{
str = h.mc_object,
nbr = (int)h.avg // Average returns a double
}).Take(50).ToList();
}
请注意,我已将 &
更改为 &&
。对于订购我不确定。我不需要查询后半部分的完整数据,所以我添加了注释 data = g
您好,我有以下问题
var myList = (from p in db.Full
where (p.date_reception > begin & p.date_reception < end & !p.mc_object.Contains("NULL")
& (!strListe.Contains(p.mc_object)))
group p by new { p.mc_object} into g
select g.OrderByDescending(p => new {p.duration,p.mc_object} ) into r
select new StringIntType
{
str = r.mc_object,
nbr = r.duration.Value
}).Take(50).ToList();
我需要按 mc_object 和 select mc_object 分组,平均持续时间 并按平均持续时间降序排列,感谢您的帮助
查询应该是
var myList = (from p in db.Full
// Don't use &! Use &&
where p.date_reception > begin &&
p.date_reception < end &&
!p.mc_object.Contains("NULL") &&
!strListe.Contains(p.mc_object)
group p by p.mc_object into g
select new
{
mc_object = g.Key,
/* data = g, */
avg = g.Average(x => x.duration)
} into h
// if you want both descending, add descending after mc_object
orderby h.avg descending, h.mc_object
select new StringIntType
{
str = h.mc_object,
nbr = (int)h.avg // Average returns a double
}).Take(50).ToList();
}
请注意,我已将 &
更改为 &&
。对于订购我不确定。我不需要查询后半部分的完整数据,所以我添加了注释 data = g