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var ss = from r in db.Am_recProScheme
         select r;
//2
var ss1 = db.Am_recProScheme;
//3
string sssql = "select * from Am_recProScheme";

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var ss = from r in db.Am_recProScheme
         where r.rpId > 10
         select r;
//2
var ss1 = db.Am_recProScheme.Where(p => p.rpId > 10);
//3
string sssql = "select * from Am_recProScheme where rpid>10";

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//获取最大的rpId
var ss = (from r in db.Am_recProScheme
          select r).Max(p => p.rpId);
//获取最小的rpId
var ss = (from r in db.Am_recProScheme
          select r).Min(p => p.rpId);
//获取结果集的总数
var ss = (from r in db.Am_recProScheme                  
         select r).Count();
//获取rpId的和
var ss = (from r in db.Am_recProScheme
          select r).Sum(p => p.rpId);
//2
var ss1 = db.Am_recProScheme.Max(p=>p.rpId);
var ss1 = db.Am_recProScheme.Min(p => p.rpId);
var ss1 = db.Am_recProScheme.Count() ;
var ss1 = db.Am_recProScheme.Sum(p => p.rpId);
Response.Write(ss);
//3
string sssql = "select max(rpId) from Am_recProScheme";
       sssql = "select min(rpId) from Am_recProScheme";
       sssql = "select count(1) from Am_recProScheme";
       sssql = "select sum(rpId) from Am_recProScheme";

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var ss = from r in db.Am_recProScheme
         where r.rpId > 10
         orderby r.rpId descending  //倒序 //ascending //正序
         select r;
//正序
var ss1 = db.Am_recProScheme.OrderBy(p => p.rpId).Where(p => p.rpId > 10).ToList();
//倒序
var ss2 = db.Am_recProScheme.OrderByDescending(p => p.rpId).Where(p => p.rpId > 10).ToList();
            
string sssql = "select * from Am_recProScheme where rpid>10 order by rpId [desc|asc]";

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//如果取最后一个可以按倒叙排列再取值
var ss = (from r in db.Am_recProScheme                     
          select r).FirstOrDefault();
//（）linq to ef 好像不支持 Last() 
var ss1 = db.Am_recProScheme.FirstOrDefault();
//var ss1 = db.Am_recProScheme.First(); 
string sssql = "select top(1) * from Am_recProScheme";

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var ss = (from r in db.Am_recProScheme
          orderby r.rpId descending
          select r).Skip(10); //跳过前10条数据，取10条之后的所有数据 
//2 
var ss1 = db.Am_recProScheme.OrderByDescending(p => p.rpId).Skip(10).ToList();
//3
string sssql = "select * from (select ROW_NUMBER()over(order by rpId desc) as rowNum, * from [Am_recProScheme]) as t where rowNum>10";

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var ss = (from r in db.Am_recProScheme
          where r.rpId > 10
          orderby r.rpId descending
          select r).Skip(10).Take(10); //取第11条到第20条数据 
//2 Take(10): 数据从开始获取，获取指定数量（10）的连续数据
var ss1 = db.Am_recProScheme.OrderByDescending(p => p.rpId).Where(p => p.rpId > 10).Skip(10).Take(10).ToList();
//3
string sssql = "select * from (select ROW_NUMBER()over(order by rpId desc) as rowNum, * from [Am_recProScheme]) as t where rowNum>10 and rowNum<=20";

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var ss = from r in db.Am_recProScheme
         where r.SortsText.Contains("张")
         select r;
//2
var ss1 = db.Am_recProScheme.Where(p => p.SortsText.Contains("张")).ToList();
//3
string sssql = "select * from Am_recProScheme where SortsText like '%张%'";

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var ss = from r in db.Am_recProScheme
         orderby r.rpId descending
         group r by r.recType into n
         select new
         {
             n.Key,  //这个Key是recType
             rpId = n.Sum(r => r.rpId), //组内rpId之和
             MaxRpId = n.Max(r => r.rpId),//组内最大rpId
             MinRpId = n.Min(r => r.rpId), //组内最小rpId
         };
            foreach (var t in ss)
{
    Response.Write(t.Key + "--" + t.rpId + "--" + t.MaxRpId + "--" + t.MinRpId);
}
//2
var ss1 = from r in db.Am_recProScheme
         orderby r.rpId descending
         group r by r.recType into n
         select n;
foreach (var t in ss1)
{
    Response.Write(t.Key + "--" + t.Min(p => p.rpId));
}
//3
var ss2 = db.Am_recProScheme.GroupBy(p => p.recType);
foreach (var t in ss2)
{
    Response.Write(t.Key + "--" + t.Min(p => p.rpId));
}
//4
string sssql = "select recType,min(rpId),max(rpId),sum(rpId) from Am_recProScheme group by recType";

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var ss = from r in db.Am_recProScheme
         join w in db.Am_Test_Result on r.rpId equals w.rsId
         orderby r.rpId descending
         select r;
//2
var ss1 = db.Am_recProScheme.Join(db.Am_Test_Result, p => p.rpId, r => r.rsId, (p, r) => p).OrderByDescending(p => p.rpId).ToList();
//3
string sssql = "select r.* from [Am_recProScheme] as r inner join [dbo].[Am_Test_Result] as t on r.[rpId] = t.[rsId] order by r.[rpId] desc";

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var ss = from p in db.Am_recProScheme
 where (new int?[] { 24, 25,26 }).Contains(p.rpId)
 select p;
foreach (var p in ss)
{
    Response.Write(p.Sorts);
}
//2
string st = "select * from Am_recProScheme where rpId in(24,25,26)";