Linq to sql 将存储过程转换为Linq2SQL(计数、最大值、组、orderby)
我有两张桌子Linq to sql 将存储过程转换为Linq2SQL(计数、最大值、组、orderby),linq-to-sql,count,group-by,inner-join,max,Linq To Sql,Count,Group By,Inner Join,Max,我有两张桌子 CREATE TABLE master (idMaster int identity (1,1) not null, TheName varchar( 100) null, constraint pk_master primary key(idMaster) clustered) 及- CREATE TABLE lnk (idSlave int not null, idMaster int not null, constraint pk_lnk_master_slave(
CREATE TABLE master (idMaster int identity (1,1) not null,
TheName varchar( 100) null,
constraint pk_master primary key(idMaster) clustered)
及-
CREATE TABLE lnk (idSlave int not null,
idMaster int not null,
constraint pk_lnk_master_slave(idSlave) primary key clustered)
Master.idMaster和lnk.idMaster之间的链接
我有一个SQL查询:
select max (master.idMaster) as idMaster,
master.theName,
count (lnk.idSlave) as freq
from lnk
inner join master ON lnk.idMaster = master.idMaster
Group by master.theName
order by freq desc, master.theName
我需要将此T-SQL查询转换为Linq to SQL语句,最好是在C中,您无法控制Linq to SQL查询的确切SQL输出,但这应该可以做到:
var results = from slave in dataContext.lnks
group slave by slave.idMaster
into slaveByMaster
let count = slaveByMaster.Count()
orderby count
select new
{
slaveByMaster.Key,
count,
};
您仍然需要另一个查询来计算maxmaster.idMaster。大概是这样的:
var result2 = (from master in dataContext.masters
select master.idMaster).Max();