描述：查詢顧客的國家、城市和訂單數資訊，要求國家是法國並且訂單數大於5
查詢句法：
var 多條件= from c in ctx.customers
where c.country == "france" && c.orders.count > 5
select new ;
對應sql：
select [t0].[country], [t0].[city], (
select count(*)
from [dbo].[orders] as [t2]
where [t2].[customerid] = [t0].[customerid]
) as [value]
from [dbo].[customers] as [t0]
where ([t0].[country] = @p0) and (((
select count(*)
from [dbo].[orders] as [t1]
where [t1].[customerid] = [t0].[customerid]
)) > @p1)
-- @p0: input string (size = 6; prec = 0; scale = 0) [france]
-- @p1: input int32 (size = 0; prec = 0; scale = 0) [5]
orderby
描述：查詢所有沒有下屬雇員的雇用年和名，按照雇用年倒序，按照名正序
查詢句法：
var 排序= from emp in ctx.employees
where emp.employees.count == 0
orderby emp.hiredate.value.year descending, emp.firstname ascending
select new ;
對應sql：
select datepart(year, [t0].[hiredate]) as [value], [t0].[firstname]
from [dbo].[employees] as [t0]
where ((
select count(*)
from [dbo].[employees] as [t1]
where [t1].[reportsto] = [t0].[employeeid]
)) = @p0
order by datepart(year, [t0].[hiredate]) desc, [t0].[firstname]
-- @p0: input int32 (size = 0; prec = 0; scale = 0) [0]
分頁
描述：按照每頁10條記錄，查詢第二頁的顧客
查詢句法：
var 分頁= (from c in ctx.customers select c).skip(10).take(10);
對應sql：
select top 10 [t1].[customerid], [t1].[companyname], [t1].[contactname], [t1].[contacttitle], [t1].[address], [t1].[city], [t1].[region], [t1].[postalcode], [t1].[country], [t1].[phone], [t1].[fax]
from (
select row_number() over (order by [t0].[customerid], [t0].[companyname], [t0].[contactname], [t0].[contacttitle], [t0].[address], [t0].[city], [t0].[region], [t0].[postalcode], [t0].[country], [t0].[phone], [t0].[fax]) as [row_number], [t0].[customerid], [t0].[companyname], [t0].[contactname], [t0].[contacttitle], [t0].[address], [t0].[city], [t0].[region], [t0].[postalcode], [t0].[country], [t0].[phone], [t0].[fax]
from [dbo].[customers] as [t0]
) as [t1]
where [t1].[row_number] > @p0
-- @p0: input int32 (size = 0; prec = 0; scale = 0) [10]
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