Question

我正在尝试将SQL查询转换为LINQ，但是我需要利用HAVING Count（Distinct），这在LINQ中无法实现，而且我似乎找不到替代方法来获得相同的结果

       SELECT 
       B.BranchCode ,
       B.BranchName ,
       rv.ENGINEER ,
       CONVERT ( DATE, rv.VISITDATE ) [Date] ,
       CONVERT ( TIME, rv.STARTTIME ) [Start] ,
       COUNT ( DISTINCT rv.VISITID )  V
       FROM
       dbo.ltbl_Branch                 AS B
       INNER JOIN dbo.tbl_contract     AS C ON C.BranchCode = B.BranchCode
       INNER JOIN dbo.tbl_repair_order AS r ON r.CONTRACT   = C.Contract
       INNER JOIN dbo.tbl_repair_visit AS rv ON rv.ORDERID  = r.ORDERID
       WHERE
       CONVERT ( DATE, rv.VISITDATE ) BETWEEN '2019-02-01'
                                      AND     '2019-02-01'
       AND ISNULL ( rv.FromHHT, 0 ) = 0
                    GROUP BY
                        B.BranchCode ,
                        B.BranchName ,
                        rv.ENGINEER ,
                        CONVERT ( DATE, rv.VISITDATE ) ,
                        CONVERT ( TIME, rv.STARTTIME )
                    HAVING
                        COUNT ( DISTINCT rv.VISITID ) > 1

上面是我要转换的SQL查询，到目前为止，我拥有的LINQ查询在下面

from b in Ltbl_Branches
join c in Tbl_contracts on b.BranchCode equals c.BranchCode
join r in Tbl_repair_orders on c.Contract equals r.CONTRACT
join rv in Tbl_repair_visits on r.ORDERID equals rv.ORDERID
where rv.VISITDATE >= DateTime.Today.AddDays(-123)
      && rv.VISITDATE <= DateTime.Today.AddDays(-122)
      && rv.FromHHT == false
group b by new { b.BranchCode, b.BranchName, rv.ENGINEER, rv.VISITDATE, 
rv.STARTTIME } into g
where g.Count() > 1
select new {
        BranchCode = g.Key.BranchCode,
        BranchName = g.Key.BranchName,
        Engineer = g.Key.ENGINEER,
        Date = g.Key.VISITDATE,
        Time = g.Key.STARTTIME,
        V =  g.Count()
       }

我正在努力在linq上工作的原因是Whileing Count（DISTINCT rv.VISITID）> 1，我认为其余代码都按预期工作。

我正在从网络上的数据库中提取数据，由于它具有重复的条目，因此2月1日目前只是一个随机日期，而从.AddDays（-123）来自的日期开始，当前是123 。这两个查询返回不同的结果，SQL查询返回的计数为170，而我的LINQ查询仅返回98。

LINQ中的Count（Distinct x）

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