我可以一起使用两个Orderby条件吗 [英] Can I Use Two Orderby Condition Together

问题描述

我想知道有什么方法可以通过new id()使用order和通过< column name =">

i want to know is there any way to used orderby new id() and order by <column name=""> with together????

推荐答案

您可以按两列进行排序，例如select * from table1 order by colA,colB

You can order by two columns for e.g. select * from table1 order by colA,colB

我认为您应该更具体一点^ _ ^

C#linq

I think you should be a bit more specific ^_^

C# linq

  private int TypeValue(string type){
    switch(type.ToLower()){
       case "bird":
         return 0;
       case "flower":
         return 1;
       case "animal":
         return 2;
       case "vegitable":
         return 3;
       default:
         return 100;
    }
}
....
  list = list.OrderBy(i=>TypeValue(i.type)).ThenBy(i=>i.newId);

//paging

  list = list.skip(pageIndex * pageSize).take(pageSize);

c#DataTable

c# DataTable

  DataTable dt= new DataTable();


foreach (DataRow row in DT.Rows){
    row("CalculatedColumnName") = TypeValue(row.type);
} 
  DataView dv = new DataView(dt);


  dv.Sort = "CalculatedColumnName, newIdASC";
  
  //paging
  var paging = dv.AsEnumerable().skip(pageIndex * pageSize).take(pageSize)

SQL

Sql

   Select *,
    case type
      when 'bird' then 0
      when 'flower' then 1
      when 'animal' then 2
      when 'vegitable' then 3
    end as TypeSort

 from list
   order by 
    case type 
      when 'bird' then 0
      when 'flower' then 1
      when 'animal' then 2
      when 'vegitable' then 3
    end
-- Yes you do have to type it out again (without the name), unless you use common table expressions (cte) but this is simpler
, newId

带CTE的SQL
您将需要将其创建为存储过程

SQL with CTE
You will need to create this as a stored procedure

Sql
<pre lang="SQL">
with firstCTE as ( -- just to get the data and sort column
   Select *,
    case type
      when 'bird' then 0
      when 'flower' then 1
      when 'animal' then 2
      when 'vegitable' then 3
    end as TypeSort
 from list
),
secondCTE as ( -- to set up the RowNumber
   select * , 
   ROW_NUMBER() OVER (ORDER BY TypeSort, newId) AS RowNumber
   -- this will give the items a RowNumber in order of the sort
   from firstCTE 
)
select * from secondCTE
where RowNumber >= (@PageStart * @PageSize) AND RowNumber < ((@PageStart+1) * @PageSize)
order by RowNumber

--This is very inexpensive as the cte's are like views and won't select any data until the last 'select'

javascript

javascript

    var sortbyVat= function(a, b){
        a= a.VatRate;
        b= b.VatRate;
        if(a== b) return 0;
        return a> b? 1:-1;
    }
    var sortbyPriceAndVat= function(a, b){
        a= a.Price;
        b= b.Price;
        if(a== b) return sortbyVat(a,b);
        return a> b? 1:-1;
    }

...

    array.sort(sortbyPriceAndVat);

更新了c#以供特定用途

updated c# for specific use

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