使用两个实体的慢LINQ查询

Question

此查询非常慢。可以帮助我不知道从哪里开始。当删除.Include（“Pessoa”）时，返回非常快。

[Table("Pessoa")]
public class Pessoa
{

    public int PessoaId { get; set; }

    public string NomPessoa { get; set; }

    public string FlgTipoPessoa { get; set; }

    public DateTime DatCadastro { get; set; }

    public string ObsPessoa { get; set; }

    public virtual ICollection<Endereco> Enderecos { get; set; }

    public Pessoa()
    {
        Enderecos = new List<Endereco>();
    }

}

[Table("PessoaFisica")]
public class PessoaFisica : Pessoa
{

    public string NumCpf { get; set; }

    public string NumRg { get; set; }

    public DateTime? DatNascimento { get; set; }

    public string FlgSexo { get; set; }

}

[Table("PessoaJuridica")]
public class PessoaJuridica : Pessoa
{
    public string NumCnpj { get; set; }

    public string NumInscricaoEstadual { get; set; }

    public string NumInscricaoMunicipal { get; set; }

}

 [Table("Funcionario")]
public class Funcionario : PessoaFisica
{
    public DateTime DatAdmissao { get; set; }
    public DateTime? DatDemissao { get; set; }
    public decimal PercRoyalty { get; set; }
}

[Table("FluxoDeCaixa")]
public class FluxoDeCaixa
{
    public int FluxoDeCaixaId { get; set; }

    public int PlanoDeContasId { get; set; }
    public PlanoDeContas PlanoDeContas { get; set; }

    public string DscFluxoDeCaixa { get; set; }

    public int FuncionarioId { get; set; }
    [ForeignKey("FuncionarioId")]
    public Funcionario Funcionario { get; set; }


    public decimal ValFluxoDeCaixa { get; set; }
    public DateTime DatEmissao { get; set; }
    public DateTime DatVencimento { get; set; }
    public DateTime DatFluxo { get; set; }

    public int PessoaId { get; set; }
    [ForeignKey("PessoaId")]
    public virtual Pessoa Pessoa { get; set; }

    public string NumDocto { get; set; }
    public string NumCheque { get; set; }
    public string FlgSituacaoCheque { get; set; }
    public string ObsFluxoDeCaixa { get; set; }        
}

public override IQueryable<Entity.Modelos.FluxoDeCaixa> Filtro(System.Linq.Expressions.Expression<System.Func<Entity.Modelos.FluxoDeCaixa, bool>> expressao)
    {
        return _contexto.FluxoDeCaixa.Include("Pessoa").Where(expressao);
    }

.Filtro(f => f.DatFluxo >= dataInicial.Date && f.DatFluxo <= dataFinal.Date).ToList();

这是实体框架生成的查询，我不明白为什么使用这么多Left Join。我相信这是缓慢的原因。

{SELECT 
[Extent1].[FluxoDeCaixaId] AS [FluxoDeCaixaId], 
[Extent1].[PlanoDeContasId] AS [PlanoDeContasId], 
[Extent1].[DscFluxoDeCaixa] AS [DscFluxoDeCaixa], 
[Extent1].[FuncionarioId] AS [FuncionarioId], 
[Extent1].[ValFluxoDeCaixa] AS [ValFluxoDeCaixa], 
[Extent1].[DatEmissao] AS [DatEmissao], 
[Extent1].[DatVencimento] AS [DatVencimento], 
[Extent1].[DatFluxo] AS [DatFluxo], 
[Extent1].[PessoaId] AS [PessoaId], 
[Extent1].[NumDocto] AS [NumDocto], 
[Extent1].[NumCheque] AS [NumCheque], 
[Extent1].[FlgSituacaoCheque] AS [FlgSituacaoCheque], 
[Extent1].[ObsFluxoDeCaixa] AS [ObsFluxoDeCaixa], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN N'2X' WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN N'2X0X' WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN N'2X0X0X' ELSE N'2X1X' END AS [C1], 
[Join3].[PessoaId1] AS [PessoaId1], 
[Join3].[NomPessoa] AS [NomPessoa], 
[Join3].[FlgTipoPessoa] AS [FlgTipoPessoa], 
[Join3].[DatCadastro] AS [DatCadastro], 
[Join3].[ObsPessoa] AS [ObsPessoa], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS nvarchar(1)) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN [Join3].[NumCpf] WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN [Join3].[NumCpf] END AS [C2], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS nvarchar(1)) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN [Join3].[NumRg] WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN [Join3].[NumRg] END AS [C3], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS datetime) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN [Join3].[DatNascimento] WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN [Join3].[DatNascimento] END AS [C4], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS nvarchar(1)) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN [Join3].[FlgSexo] WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN [Join3].[FlgSexo] END AS [C5], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS datetime) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN CAST(NULL AS datetime) WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN [Join3].[DatAdmissao] END AS [C6], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS datetime) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN CAST(NULL AS datetime) WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN [Join3].[DatDemissao] END AS [C7], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS decimal(18,2)) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN CAST(NULL AS decimal(18,2)) WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN [Join3].[PercRoyalty] END AS [C8], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS nvarchar(1)) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN CAST(NULL AS nvarchar(1)) WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN CAST(NULL AS nvarchar(1)) ELSE [Join3].[NumCnpj] END AS [C9], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS nvarchar(1)) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN CAST(NULL AS nvarchar(1)) WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN CAST(NULL AS nvarchar(1)) ELSE [Join3].[NumInscricaoEstadual] END AS [C10], 
CASE WHEN (( NOT (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL))) AND ( NOT (([Join3].[C12] = 1) AND ([Join3].[C12] IS NOT NULL)))) THEN CAST(NULL AS nvarchar(1)) WHEN (([Join3].[C11] = 1) AND ([Join3].[C11] IS NOT NULL) AND ( NOT (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)))) THEN CAST(NULL AS nvarchar(1)) WHEN (([Join3].[C2] = 1) AND ([Join3].[C2] IS NOT NULL)) THEN CAST(NULL AS nvarchar(1)) ELSE [Join3].[NumInscricaoMunicipal] END AS [C11]
FROM  [FluxoDeCaixa] AS [Extent1]
INNER JOIN  (SELECT [Extent2].[PessoaId] AS [PessoaId1], [Extent2].[NomPessoa] AS [NomPessoa], [Extent2].[FlgTipoPessoa] AS [FlgTipoPessoa], [Extent2].[DatCadastro] AS [DatCadastro], [Extent2].[ObsPessoa] AS [ObsPessoa], [Project1].[PessoaId] AS [PessoaId2], [Project1].[NumCnpj] AS [NumCnpj], [Project1].[NumInscricaoEstadual] AS [NumInscricaoEstadual], [Project1].[NumInscricaoMunicipal] AS [NumInscricaoMunicipal], [Project1].[C1] AS [C12], [Project3].[PessoaId] AS [PessoaId3], [Project3].[NumCpf] AS [NumCpf], [Project3].[NumRg] AS [NumRg], [Project3].[DatNascimento] AS [DatNascimento], [Project3].[FlgSexo] AS [FlgSexo], [Project3].[C1] AS [C11], [Project3].[DatAdmissao] AS [DatAdmissao], [Project3].[DatDemissao] AS [DatDemissao], [Project3].[PercRoyalty] AS [PercRoyalty], [Project3].[C2] AS [C2]
    FROM   [Pessoa] AS [Extent2]
    LEFT OUTER JOIN  (SELECT 
        [Extent3].[PessoaId] AS [PessoaId], 
        [Extent3].[NumCnpj] AS [NumCnpj], 
        [Extent3].[NumInscricaoEstadual] AS [NumInscricaoEstadual], 
        [Extent3].[NumInscricaoMunicipal] AS [NumInscricaoMunicipal], 
        cast(1 as bit) AS [C1]
        FROM [PessoaJuridica] AS [Extent3] ) AS [Project1] ON [Extent2].[PessoaId] = [Project1].[PessoaId]
    LEFT OUTER JOIN  (SELECT 
        [Extent4].[PessoaId] AS [PessoaId], 
        [Extent4].[NumCpf] AS [NumCpf], 
        [Extent4].[NumRg] AS [NumRg], 
        [Extent4].[DatNascimento] AS [DatNascimento], 
        [Extent4].[FlgSexo] AS [FlgSexo], 
        cast(1 as bit) AS [C1], 
        [Project2].[DatAdmissao] AS [DatAdmissao], 
        [Project2].[DatDemissao] AS [DatDemissao], 
        [Project2].[PercRoyalty] AS [PercRoyalty], 
        CASE WHEN (([Project2].[C1] = 1) AND ([Project2].[C1] IS NOT NULL)) THEN cast(1 as bit) WHEN ( NOT (([Project2].[C1] = 1) AND ([Project2].[C1] IS NOT NULL))) THEN cast(0 as bit) END AS [C2]
        FROM  [PessoaFisica] AS [Extent4]
        LEFT OUTER JOIN  (SELECT 
            [Extent5].[PessoaId] AS [PessoaId], 
            [Extent5].[DatAdmissao] AS [DatAdmissao], 
            [Extent5].[DatDemissao] AS [DatDemissao], 
            [Extent5].[PercRoyalty] AS [PercRoyalty], 
            cast(1 as bit) AS [C1]
            FROM [Funcionario] AS [Extent5] ) AS [Project2] ON [Extent4].[PessoaId] = [Project2].[PessoaId] ) AS [Project3] ON [Extent2].[PessoaId] = [Project3].[PessoaId] ) AS [Join3] ON [Extent1].[PessoaId] = [Join3].[PessoaId1]
WHERE ([Extent1].[DatFluxo] >= @p__linq__0) AND ([Extent1].[DatFluxo] <= @p__linq__1)}

Answer 1

您的问题可能是由于在数据模型中使用Table Per Type（TPT）继承。我现在正在努力解决类似的问题。为了在选择基类型时实现正确的派生类型，实体框架将基类型表与每个可能的派生表连接起来，除非您使用OfType<>()方法。

context.BaseEntities.OfType<DerivedEntityX>();

我发现最好只在简单的情况下使用TPT，其中没有太多的派生类型，并且只有一个继承深度。您在哪里使用TPT尝试并仅执行简单查询。您可能会发现预生成视图可能会减少您的初始冷查询执行时间。投影到匿名类型或视图模型，您可以在其中仅选择必要的属性和/或使用OfType<>()方法，这对提高性能也很有用。当然，您也可以考虑使用Table Per Heirarchy（TPH），以便所有派生类型映射到单个表。

Answer 2

首先，如果您不需要查询Pessoa，请不要包含它。

其次，这可能是因为您的Pessoa实体的以下属性：

public virtual ICollection<Endereco> Enderecos { get; set; }

由于您将Enderecos声明为虚拟，因此每次查询Pessoa实体时都会延迟加载。

有关加载相关属性的详情，请参阅this链接。

Answer 3

不确定您使用的是哪种版本，但

1）在db中有适当的索引，使用生成的sql作为有效负载（修改为硬编码参数）： Using Database Engine Tuning Advisor

2）如果你直接使用objectcontext，那么这可能会加快速度（取决于日期范围的大小）然后像这样修改Filtro体：

var dataList= _contexto.FluxoDeCaixa.Where(expressao).ToList();

for (int x = 0; x < dataList.Count; x++)
     _contexto.LoadProperty(dataList[x], p => p.Pessoa);

return dataList;

3）理想情况下，如果你想获得最大性能，重做它，这样你就不需要返回每一列，只返回所需的内容，如：

_contexto.FluxoDeCaixa.Select(t => new { t.DatFluxo , t.DatVencimento}).Where ....