我有一个对数据库的查询，需要花费大量时间来返回结果。查询是通过实体框架6创建的，但我已经获得了生成的查询，并且我在SQL Management Studio中测试了查询。
在做了一些测试后，我意识到当我从连接中退出特定的表时，查询的工作时间不到一秒，如果不是，查询的时间超过30秒。
我的第一个想法是该表的主键没有索引，但是数据库模式是通过EF迁移创建的，因此所有主键都有正确的索引。
这是查询
SELECT TOP (10)
[Join4].[Id1] AS [Id],
[Join4].[Title] AS [Title],
[Join4].[IdServiceType] AS [IdServiceType],
[Join4].[Description] AS [Description],
[Join4].[DescriptionLarge] AS [DescriptionLarge],
[Join4].[DescriptionAgency] AS [DescriptionAgency],
[Join4].[DescriptionCentral] AS [DescriptionCentral],
[Join4].[Pvp] AS [Pvp],
[Join4].[PreviousPvp] AS [PreviousPvp],
[Join4].[PriceAgency] AS [PriceAgency],
[Join4].[PriceProvider] AS [PriceProvider],
[Join4].[PriceSamurai] AS [PriceSamurai],
[Join4].[IdProvider] AS [IdProvider],
[Join4].[IdDestination] AS [IdDestination],
[Join4].[IdOrigin] AS [IdOrigin],
[Join4].[ExpirationDate] AS [ExpirationDate],
[Join4].[DistanceToCenter] AS [DistanceToCenter],
[Join4].[Longitude1] AS [Longitude],
[Join4].[Latitude1] AS [Latitude],
[Join4].[CreationDate] AS [CreationDate],
[Join4].[ValidationDateStart] AS [ValidationDateStart],
[Join4].[ValidationDateEnd] AS [ValidationDateEnd],
[Join4].[ExecutionDateStart] AS [ExecutionDateStart],
[Join4].[ExecutionDateEnd] AS [ExecutionDateEnd],
[Join4].[Nights] AS [Nights],
[Join4].[Document] AS [Document],
[Join4].[Id2] AS [Id1],
[Join4].[Code1] AS [Code],
[Join4].[Name1] AS [Name],
[Join4].[IdSuperDestination1] AS [IdSuperDestination],
[Join4].[Iata1] AS [Iata],
[Join4].[Level1] AS [Level],
[Join4].[IdDestinationType1] AS [IdDestinationType],
[Join4].[TouristInfo1] AS [TouristInfo],
[Join4].[Longitude2] AS [Longitude1],
[Join4].[Latitude2] AS [Latitude1],
[Join4].[Language1] AS [Language],
[Join4].[IdCurrency1] AS [IdCurrency],
[Join4].[CurrencyName1] AS [CurrencyName],
[Join4].[Vaccine1] AS [Vaccine],
[Join4].[Visa1] AS [Visa],
[Join4].[Embassy1] AS [Embassy],
[Join4].[Recommendations1] AS [Recommendations],
[Join4].[Id3] AS [Id2],
[Join4].[Code2] AS [Code1],
[Join4].[Name2] AS [Name1],
[Join4].[IdSuperDestination2] AS [IdSuperDestination1],
[Join4].[Iata2] AS [Iata1],
[Join4].[Level2] AS [Level1],
[Join4].[IdDestinationType2] AS [IdDestinationType1],
[Join4].[TouristInfo2] AS [TouristInfo1],
[Join4].[Longitude3] AS [Longitude2],
[Join4].[Latitude3] AS [Latitude2],
[Join4].[Language2] AS [Language1],
[Join4].[IdCurrency2] AS [IdCurrency1],
[Join4].[CurrencyName2] AS [CurrencyName1],
[Join4].[Vaccine2] AS [Vaccine1],
[Join4].[Visa2] AS [Visa1],
[Join4].[Embassy2] AS [Embassy1],
[Join4].[Recommendations2] AS [Recommendations1],
[Join4].[Id4] AS [Id3],
[Join4].[Name3] AS [Name2],
[Join4].[Id5] AS [Id4],
[Join4].[Name4] AS [Name3],
[Join4].[Observations] AS [Observations],
[Join4].[Address] AS [Address],
[Join4].[Web] AS [Web],
[Join4].[Phone] AS [Phone],
[Join4].[Mobile] AS [Mobile],
[Join4].[Fax] AS [Fax],
[Join4].[Email] AS [Email],
[Join4].[EmailBook] AS [EmailBook],
[Join4].[Cif] AS [Cif],
[Join4].[Contact] AS [Contact],
[Join4].[Account] AS [Account],
[Join4].[AccountIban] AS [AccountIban],
[Join4].[City] AS [City],
[Join4].[Province] AS [Province],
[Join4].[CorporateName] AS [CorporateName],
[Join4].[PostalCode] AS [PostalCode],
[Join4].[Code3] AS [Code2]
FROM ( SELECT [Extent1].[Id] AS [Id1], [Extent1].[Title] AS [Title], [Extent1].[IdServiceType] AS [IdServiceType], [Extent1].[Description] AS [Description], [Extent1].[DescriptionLarge] AS [DescriptionLarge], [Extent1].[DescriptionAgency] AS [DescriptionAgency], [Extent1].[DescriptionCentral] AS [DescriptionCentral], [Extent1].[Pvp] AS [Pvp], [Extent1].[PreviousPvp] AS [PreviousPvp], [Extent1].[PriceAgency] AS [PriceAgency], [Extent1].[PriceProvider] AS [PriceProvider], [Extent1].[PriceSamurai] AS [PriceSamurai], [Extent1].[IdProvider] AS [IdProvider], [Extent1].[IdDestination] AS [IdDestination], [Extent1].[IdOrigin] AS [IdOrigin], [Extent1].[ExpirationDate] AS [ExpirationDate], [Extent1].[DistanceToCenter] AS [DistanceToCenter], [Extent1].[Longitude] AS [Longitude1], [Extent1].[Latitude] AS [Latitude1], [Extent1].[CreationDate] AS [CreationDate], [Extent1].[ValidationDateStart] AS [ValidationDateStart], [Extent1].[ValidationDateEnd] AS [ValidationDateEnd], [Extent1].[ExecutionDateStart] AS [ExecutionDateStart], [Extent1].[ExecutionDateEnd] AS [ExecutionDateEnd], [Extent1].[Nights] AS [Nights], [Extent1].[Document] AS [Document], [Extent2].[Id] AS [Id2], [Extent2].[Code] AS [Code1], [Extent2].[Name] AS [Name1], [Extent2].[IdSuperDestination] AS [IdSuperDestination1], [Extent2].[Iata] AS [Iata1], [Extent2].[Level] AS [Level1], [Extent2].[IdDestinationType] AS [IdDestinationType1], [Extent2].[TouristInfo] AS [TouristInfo1], [Extent2].[Longitude] AS [Longitude2], [Extent2].[Latitude] AS [Latitude2], [Extent2].[Language] AS [Language1], [Extent2].[IdCurrency] AS [IdCurrency1], [Extent2].[CurrencyName] AS [CurrencyName1], [Extent2].[Vaccine] AS [Vaccine1], [Extent2].[Visa] AS [Visa1], [Extent2].[Embassy] AS [Embassy1], [Extent2].[Recommendations] AS [Recommendations1], [Extent3].[Id] AS [Id3], [Extent3].[Code] AS [Code2], [Extent3].[Name] AS [Name2], [Extent3].[IdSuperDestination] AS [IdSuperDestination2], [Extent3].[Iata] AS [Iata2], [Extent3].[Level] AS [Level2], [Extent3].[IdDestinationType] AS [IdDestinationType2], [Extent3].[TouristInfo] AS [TouristInfo2], [Extent3].[Longitude] AS [Longitude3], [Extent3].[Latitude] AS [Latitude3], [Extent3].[Language] AS [Language2], [Extent3].[IdCurrency] AS [IdCurrency2], [Extent3].[CurrencyName] AS [CurrencyName2], [Extent3].[Vaccine] AS [Vaccine2], [Extent3].[Visa] AS [Visa2], [Extent3].[Embassy] AS [Embassy2], [Extent3].[Recommendations] AS [Recommendations2], [Extent4].[Id] AS [Id4], [Extent4].[Name] AS [Name3], [Extent5].[Id] AS [Id5], [Extent5].[Name] AS [Name4], [Extent5].[Observations] AS [Observations], [Extent5].[Address] AS [Address], [Extent5].[Web] AS [Web], [Extent5].[Phone] AS [Phone], [Extent5].[Mobile] AS [Mobile], [Extent5].[Fax] AS [Fax], [Extent5].[Email] AS [Email], [Extent5].[EmailBook] AS [EmailBook], [Extent5].[Cif] AS [Cif], [Extent5].[Contact] AS [Contact], [Extent5].[Account] AS [Account], [Extent5].[AccountIban] AS [AccountIban], [Extent5].[City] AS [City], [Extent5].[Province] AS [Province], [Extent5].[CorporateName] AS [CorporateName], [Extent5].[PostalCode] AS [PostalCode], [Extent5].[Code] AS [Code3], row_number() OVER (ORDER BY [Extent1].[Id] DESC) AS [row_number]
FROM [dbo].[Services] AS [Extent1]
INNER JOIN [dbo].[Destinations] AS [Extent2] ON [Extent1].[IdDestination] = [Extent2].[Id]
LEFT OUTER JOIN [dbo].[Destinations] AS [Extent3] ON [Extent1].[IdOrigin] = [Extent3].[Id]
INNER JOIN [dbo].[ServiceTypes] AS [Extent4] ON [Extent1].[IdServiceType] = [Extent4].[Id]
INNER JOIN [dbo].[Providers] AS [Extent5] ON [Extent1].[IdProvider] = [Extent5].[Id]
) AS [Join4]
WHERE [Join4].[row_number] > 0
ORDER BY [Join4].[Id1] DESC
当我删除表格＆＃34;提供商＆＃34;来自＆＃34;来自＆＃34; claumule查询在不到一秒的时间内完成，但如果不是，则查询需要花费很多时间。
有什么想法吗？