通过静态列和分组列进行分组 [英] Group by with static columns and grouped columns
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问题描述
我已经习惯了sql,还不太习惯linq.请问如何根据值对列进行分组,并将其他列分组到列表中并使其他列静态化?
I'm use to sql, and not quite used to linq yet. May I ask how do I group columns based on a value, and group other columns to a list and make the other columns static?
例如
People | Businesses | StreetAddress
John | Store 1 | Hello Blvd.
John | Store 2 | Hello Blvd.
生产
People | Businesses | StreetAddress
John | ["Store 1", "Store 2"] | Hello Blvd.
我的linq查询制作表1
My linq query to make Table 1
from x in ctx.People
join ownership in ctx.Ownerships
on x.Id equals ownership.Owner_Id into ps
from ownership in ps.DefaultIfEmpty()
join Business in ctx.Businesses
on ownership.Business_Id equals Business.Id into ps2
from Business in ps2.DefaultIfEmpty()
select new PersonDTO
{
Id = x.Id,
Business = Business.Name,
StreetAddress = x.Addresses.FirstOrDefault().Line1
}
推荐答案
假设您需要同时按人员"和街道地址.
Assuming you need to group by both People & StreetAddress.
var result = data.GroupBy(x => new { x.People, x.StreetAddress })
.ToList()
.Select(x => new
{
People = x.Key.People,
Business = String.Join(",",x.Select(z => z.Business),
StreetAddress x.Key.StreetAddress
});
修改:
在列表中获取Business
.
var result = data.GroupBy(x => new { x.People, x.StreetAddress })
.Select(x => new
{
People = x.Key.People,
Business = x.Select(z => z.Business).ToList(),
StreetAddress x.Key.StreetAddress
});
这里,数据是要分组的数据源.
Here, data is the data source you want to group.
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