Question

请帮我实现这个包含Linq中的连接和条件COUNT和SUM的SQL查询：

   SELECT  
            COUNT(distinct Spool.ISODwg+'-'+Spool.SpoolNo ) as All_Spool,
            SUM(case when (JointFMC.SBNM='AG' and JointFMC.SF='S') then JointFMC.Size else 0 end) as All_DI,
            COUNT(distinct case when (Spool.ReleaseNo is not null and Spool.ReleaseNo!='' ) then Spool.ISODwg+'-'+Spool.SpoolNo else null end) as Release_Spool,
            SUM(case when (Spool.ReleaseNo is not null and Spool.ReleaseNo!='') and (JointFMC.SBNM='AG' and JointFMC.SF='S') then JointFMC.Size else 0 end) as Release_DI,
            COUNT(distinct case when (JointFMC.RT_Status='Result Needed' or  JointFMC.RT_Status='App. Needed' ) and (JointFMC.SBNM='AG' and JointFMC.SF='S') then Spool.ISODwg+'-'+Spool.SpoolNo else null end) as BL_Spool,
            SUM(case when (JointFMC.RT_Status='Result Needed' or  JointFMC.RT_Status='App. Needed' ) and (JointFMC.SBNM='AG' and JointFMC.SF='S') then JointFMC.Size else 0 end) as BL_DI

    FROM Spool LEFT JOIN JointFMC ON (Spool.ISODwg = JointFMC.ISODwg and Spool.SpoolNo = JointFMC.SpoolNo)

假脱机类（部分）

public class Spool : ModelBase
{
    #region Properties-------------------------------------------------------------------------------
    //ISODwgNo
    private string _iSODwgNo;
    public string ISODwgNo
    {
        get { return _iSODwgNo; }
        set
        {
            if (_iSODwgNo != value)
            {
                _iSODwgNo = value;
                ValidateProperty("ISODwgNo", value);
                OnPropertyChanged("ISODwgNo");
            }
        }
    }

    //ISODwg
    private string _iSODwg;
    public string ISODwg
    {
        get { return _iSODwg; }
        set
        {
            if (_iSODwg != value)
            {
                _iSODwg = value;
                ValidateProperty("ISODwg", value);
                OnPropertyChanged("ISODwg");
            }
        }
    }

    //SpoolNo
    private string _spoolNo;
    public string SpoolNo
    {
        get { return _spoolNo; }
        set
        {
            if (_spoolNo != value)
            {
                _spoolNo = value;
                ValidateProperty("SpoolNo", value);
                OnPropertyChanged("SpoolNo");
            }
        }
    }


    //Type
    private string _type;
    public string Type
    {
        get { return _type; }
        set
        {
            if (_type != value)
            {
                _type = value;
                ValidateProperty("Type", value);
                OnPropertyChanged("Type");
            }
        }
    }


    //Area
    private string _area;
    public string Area
    {
        get { return _area; }
        set
        {
            if (_area != value)
            {
                _area = value;
                ValidateProperty("Area", value);
                OnPropertyChanged("Area");
            }
        }
    }
}

JointFMC Class（部分）

public class JointFMC : ModelBase
{
    #region Properties------------------------------------------------------
    //SBNM
    private string _sBNM;
    public string SBNM
    {
        get { return _sBNM; }
        set
        {
            if (_sBNM != value)
            {
                _sBNM = value;
                ValidateProperty("SBNM", value);
                OnPropertyChanged("SBNM");
            }
        }
    }


    //ISODwg
    private string _iSODwg;
    public string ISODwg
    {
        get { return _iSODwg; }
        set
        {
            if (_iSODwg != value)
            {
                _iSODwg = value;
                ValidateProperty("ISODwg", value);
                OnPropertyChanged("ISODwg");
            }
        }
    }


    //JointNo
    private string _jointNo;
    public string JointNo
    {
        get { return _jointNo; }
        set
        {
            if (_jointNo != value)
            {
                _jointNo = value;
                ValidateProperty("JointNo", value);
                OnPropertyChanged("JointNo");
            }
        }
    }



    //SpoolNo
    private string _spoolNo;
    public string SpoolNo
    {
        get { return _spoolNo; }
        set
        {
            if (_spoolNo != value)
            {
                _spoolNo = value;
                ValidateProperty("SpoolNo", value);
                OnPropertyChanged("SpoolNo");
            }
        }
    }


    //Size
    private double? _size;
    public double? Size
    {
        get { return _size; }
        set
        {
            if (_size != value)
            {
                _size = value;
                ValidateProperty("Size", value);
                OnPropertyChanged("Size");
            }
        }
    }


    //SF
    private string _sF;
    public string SF
    {
        get { return _sF; }
        set
        {
            if (_sF != value)
            {
                _sF = value;
                ValidateProperty("SF", value);
                OnPropertyChanged("SF");
            }
        }
    }


    //WeldRpNo
    private string _weldRpNo;
    public string WeldRpNo
    {
        get { return _weldRpNo; }
        set
        {
            if (_weldRpNo != value)
            {
                _weldRpNo = value;
                ValidateProperty("WeldRpNo", value);
                OnPropertyChanged("WeldRpNo");
            }
        }
    }


    //RT_Status
    private string _rT_Status;
    public string RT_Status
    {
        get { return _rT_Status; }
        set
        {
            if (_rT_Status != value)
            {
                _rT_Status = value;
                ValidateProperty("RT_Status", value);
                OnPropertyChanged("RT_Status");
            }
        }
    }


    #endregion

}

此致

Answer 1

这是LINQ的直接翻译：

var query =
    from Spool in db.Spool
    join JointFMC in db.JointFMC
    on new { Spool.ISODwg, Spool.SpoolNo }
    equals new { JointFMC.ISODwg, JointFMC.SpoolNo } into JointFMCJoin
    from JointFMC in JointFMCJoin.DefaultIfEmpty()
    group new { Spool, JointFMC } by 1 into g
    select new
    {
        All_Spool = g
            .Select(e => e.Spool.ISODwg + "-" + e.Spool.SpoolNo).Distinct().Count(),
        All_DI = g.Sum(e => e.JointFMC.SBNM == "AG" && e.JointFMC.SF == "S" ?
            e.JointFMC.Size : 0),
        Release_Spool = g.Where(e => !string.IsNullOrEmpty(e.Spool.ReleaseNo))
            .Select(e => e.Spool.ISODwg + "-" + e.Spool.SpoolNo).Distinct().Count(),
        Release_DI = g.Sum(e => !string.IsNullOrEmpty(e.Spool.ReleaseNo) && e.JointFMC.SBNM == "AG" && e.JointFMC.SF == "S" ?
            e.JointFMC.Size : 0),
        BL_Spool = g.Where(e => (e.JointFMC.RT_Status == "Result Needed" || e.JointFMC.RT_Status == "App. Needed") && e.JointFMC.SBNM == "AG" && e.JointFMC.SF == "S")
            .Select(e => e.Spool.ISODwg + "-" + e.Spool.SpoolNo).Distinct().Count(),
        BL_DI = g.Sum(e => (e.JointFMC.RT_Status == "Result Needed" || e.JointFMC.RT_Status == "App. Needed") && e.JointFMC.SBNM == "AG" && e.JointFMC.SF == "S" ?
            e.JointFMC.Size : 0),
    };

请注意，LINQ没有很好的SQL COUNT(DISTINCT ..)构造等价物，因此从上面的LINQ查询生成的SQL查询将比原始查询复杂得多（并且可能更慢）。在这种情况下，如果ORM工具支持LINQ并执行原始SQL查询可能会更好。

Linq加入并聚合

1 个答案: