在linq中转换SQL查询 [英] Convert SQL query in linq

问题描述

我有这个查询现在我尝试在linq中转换此查询

  ALTER   procedure  [dbo]。[spstdinfo] 
  @ year_p   int  
  as  
 选择 Catg_type.Catg_type，Program_type.Prog_name，Year_info.year，
 COUNT（std_info.catg_id） as  total_students 来自 Std_info 
  inner   join  Catg_type  on  Std_info.Catg_id = Catg_type.Catg_id 
  INNER   join  Program_type  on  Std_info.Prog_id = Program_type.Prog_id 
  inner   join  Year_info   Std_info.year_id = Year_info.year_id 
 其中 @ year_p = Year_info.year 
  group   by  Catg_type，Program_type.Prog_name，Year_info.year 

我尝试过：



i试试这个..

  var  re =（ from  stdtable  in  a.Std_info 
  join  catg  in  a.Catg_type on stdtable.Catg_id equals catg.Catg_id 
  join  prog  in  a.Program_type on stdtable.Prog_id等于prog.Prog_id 
  join  yea  in  a.Year_info on stdtable.year_id等于yea.year_id 
 选择  new  {Std_info = stdtable，catg_type = catg，Program_type = prog，Year_info = yea}）; 

现在在sql查询中有计数使用现在怎么样我在linq中使用计数





我是怎么做到的

解决方案

I我读了下面的内容，第一个有一个使用count with group by的简单例子，第二个有一个更复杂的例子



linq + C＃+ group by + count [ ^ ]

c＃ - linq with groupby and count - Stack O verflow [ ^ ]

i have this query now i try to convert this query in linq

ALTER procedure [dbo].[spstdinfo]
@year_p int
as
select Catg_type.Catg_type,Program_type.Prog_name ,Year_info.year,
COUNT(Std_info.catg_id) as total_students from Std_info 
inner join Catg_type on Std_info.Catg_id=Catg_type.Catg_id
INNER join Program_type on Std_info.Prog_id=Program_type.Prog_id
inner join Year_info on Std_info.year_id=Year_info.year_id
where @year_p=Year_info.year
group by Catg_type,Program_type.Prog_name,Year_info.year

What I have tried:

i try this ..

var re = (from  stdtable in a.Std_info
                            join catg in a.Catg_type on stdtable.Catg_id equals catg.Catg_id
                            join prog in a.Program_type on stdtable.Prog_id equals prog.Prog_id
                            join yea  in a.Year_info on stdtable.year_id equals yea.year_id
                           select new { Std_info = stdtable, Catg_type = catg,Program_type=prog,Year_info=yea });

now in sql query there is count use now how i use count in linq


how i done this

解决方案

I'd have a read of the below, the first has a simple example of using count with group by and the second has a more complex example

linq + C# + group by + count[^]
c# - linq with groupby and count - Stack Overflow[^]

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