讀這篇文章之前，我先說下，每一種搜尋結果集，我都以三種方式變現出來。
**段1：linq語句查詢；**段2：linq函式委託；**段3：sql語句查詢。
//1
var ss = from r in db.am_recproscheme
select r;
//2var ss1 = db.am_recproscheme;
//3string sssql = "select * from am_recproscheme";
//1
var ss = from r in db.am_recproscheme
where r.rpid > 10
select r;
//2var ss1 = db.am_recproscheme.where(p => p.rpid > 10);
//3string sssql = "select * from am_recproscheme where rpid>10";
//1
獲取最大的rpid
//var ss = (from r in db.am_recproscheme
// select r).max(p => p.rpid);
獲取最小的rpid
//var ss = (from r in db.am_recproscheme
// select r).min(p => p.rpid);
//獲取結果集的總數
//var ss = (from r in db.am_recproscheme
// select r).count();
//獲取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);
//3string 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";
var ss = from r in db.am_recproscheme
where r.rpid > 10
orderby r.rpid descending //倒序
// orderby r.rpid 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]";
//如果取最後乙個可以按倒敘排列再取值
var ss = (from r in db.am_recproscheme
select r).firstordefault();
//（）linq to ef 好像不支援 last()
var ss1 = db.am_recproscheme.firstordefault();
//var ss1 = db.am_recproscheme.first();
string sssql = "select top(1) * from am_recproscheme";
//1
var ss = (from r in db.am_recproscheme
orderby r.rpid descending
select r).skip(10); //跳過前10條資料，取10條之後的所有資料
//2
var ss1 = db.am_recproscheme.orderbydescending(p => p.rpid).skip(10).tolist();
//3string sssql = "select * from (select row_number()over(order by rpid desc) as rownum, * from [am_recproscheme]) as t where rownum>10";
//1
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條到第20條資料
//2 take(10): 資料從開始獲取，獲取指定數量（10）的連續資料
var ss1 = db.am_recproscheme.orderbydescending(p => p.rpid).where(p => p.rpid > 10).skip(10).take(10).tolist();
//3string sssql = "select * from (select row_number()over(order by rpid desc) as rownum, * from [am_recproscheme]) as t where rownum>10 and rownum<=20";
//1
var ss = from r in db.am_recproscheme
where r.sortstext.contains("張")
select r;
//2var ss1 = db.am_recproscheme.where(p => p.sortstext.contains("張")).tolist();
//3string sssql = "select * from am_recproscheme where sortstext like '%張%'";
//1
var ss = from r in db.am_recproscheme
orderby r.rpid descending
group r by r.rectype into n
select new
;foreach (var t in ss)
//2var 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)
//3var ss2 = db.am_recproscheme.groupby(p => p.rectype);
foreach (var t in ss2)
//4string sssql = "select rectype,min(rpid),max(rpid),sum(rpid) from am_recproscheme group by rectype";
//1
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;
//2var ss1 = db.am_recproscheme.join(db.am_test_result, p => p.rpid, r => r.rsid, (p, r) => p).orderbydescending(p => p.rpid).tolist();
//3string 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";
//1
var ss = from p in db.am_recproscheme
where (new int? ).contains(p.rpid)
select p;
foreach (var p in ss)
//2string st = "select * from am_recproscheme where rpid in(24,25,26)";
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