sql-server - 在空表上运行具有多个联接的查询时，SQL Server 挂起

Question

我们在 SQL Server 中遇到了一个有趣的错误，我想向您描述一下。我希望找出它是否真的是一个错误，如果是，我可以在哪里找到有关它的更多信息。如果它不是一个错误，我希望有人可以向我解释为什么它不是，以及我们在不知不觉中做错了什么。我似乎找不到类似问题的描述，我不确定我们是否应该向 Microsoft 报告错误或其他内容。我将首先简要描述问题，然后提供详细信息。

简而言之，问题似乎是当被连接的表的某些(大？)部分(抱歉，这里不能更具体地用数字表示)为空时，SQL Server 会阻塞包含许多连接的语句。阻塞，我的意思是它在查询中搅动和搅动，永远不会完成，这导致 SQL Server 完全停止响应。实际上，运行一次查询会导致 CPU 跳到 25% 并保持在那里。再次尝试，CPU 跳到 50%。有时，CPU 会达到 75% 或 100%，但在 50% 标记处，您甚至无法再登录到数据库服务器。

问题发生在我们使用 Hibernate(通过 Coldfusion ORM)并且有一个实体(文档)的应用程序中，该实体(文档)被分割为许多不同类型的文档。当我们在基类 Document 上运行查询(例如“FROM Document WHERE Locked=1”)时，有问题的 SQL 查询是由 Hibernate 生成的。这会导致一个很长的 SQL 查询，它将所有子类表连接在一起(下面的示例)，有时会杀死服务器。

我在测试时发现了一些有趣的事情:

只有在有大量空连接表时才会发生这种情况，这就是为什么要跟踪它的原因 - 在我们的开发或测试数据库上运行时从未发生过，因为它们有足够的数据。因此，相同的查询在一个实例中立即运行而没有问题，而在另一个实例中完全杀死 SQL 服务器。

起初我认为 SQL 查询中大量选定的列可能会导致问题，因此我使用相同的连接测试了 SQL 查询，但只从每个表中选择了一个列，因此实际上只选择了一小部分数据- 没有改善，仍然挂起。

我对几乎没有数据的数据库运行了查询，并开始一一删除连接。我发现我可以达到查询可以快速运行的程度。从这一点添加一个连接会导致查询运行，但明显变慢，重复几次最终会导致它再次停止并杀死服务器。

因此，基于上述内容，我推测 SQL Server 中存在一个错误(或一个我不知道的已知事实)，其中连接导致过多的空值会导致问题。我认为这可能是错误而不是已知限制，因为它不会导致错误消息(例如，如果您尝试在 IN 子句中查询超过 2100 个项目，您会得到)，而是挂起服务器。服务器进入 la-la 土地几乎就像连接导致了cartesion 产品，但它是相反的 - 而不是大量的数据，我没有数据。

有没有其他人遇到过这样的问题？是否有一些已知的 SQL 服务器限制，我正在摩擦？我很难用谷歌搜索这个问题，因为它很难定义。
我应该为此向 Microsoft 提交错误吗？

任何见解都非常感谢。如果需要我提供更多信息，请告诉我。

谢谢。

示例查询如下(为简洁起见，我删除了大部分选定的列):

select
    top 1 document0_.ID as ID715_,
    document0_.CreatedOn as CreatedOn715_,
    document0_.UpdatedOn as UpdatedOn715_,
    document0_.DeletedOn as DeletedOn715_,
    document0_.Deleted as Deleted715_,
    document0_.Active as Active715_,
    document0_.ActivatedOn as Activate8_715_,
    document0_.DeactivatedOn as Deactiva9_715_,
    document0_.Locked as Locked715_,
    document0_.CompletedDate as Complet11_715_,
    document0_.CreateUserID as CreateU23_715_,
    document0_.UpdateUserID as UpdateU24_715_,
    document0_1_.CreatedOn as CreatedOn717_,
    document0_1_.UpdatedOn as UpdatedOn717_,
    document0_1_.DeletedOn as DeletedOn717_,
    document0_1_.Deleted as Deleted717_,
    document0_1_.Active as Active717_,
    document0_1_.ActivatedOn as Activate7_717_,
    document0_1_.DeactivatedOn as Deactiva8_717_,
    document0_1_.Locked as Locked717_,
    document0_1_.DateReceived as DateRec10_717_,
    document0_1_.DateIssued as DateIssued717_,
    document0_1_.CreateUserID as CreateU12_717_,
    document0_1_.UpdateUserID as UpdateU13_717_,
    document0_2_.CreatedOn as CreatedOn733_,
    document0_2_.UpdatedOn as UpdatedOn733_,
    document0_2_.DeletedOn as DeletedOn733_,
    document0_2_.Deleted as Deleted733_,
    document0_2_.Active as Active733_,
    document0_2_.ActivatedOn as Activate7_733_,
    document0_2_.DeactivatedOn as Deactiva8_733_,
    document0_2_.Locked as Locked733_,
    document0_3_.CreatedOn as CreatedOn739_,
    document0_3_.UpdatedOn as UpdatedOn739_,
    document0_3_.DeletedOn as DeletedOn739_,
    document0_3_.Deleted as Deleted739_,
    document0_3_.Active as Active739_,
    document0_3_.ActivatedOn as Activate7_739_,
    document0_3_.DeactivatedOn as Deactiva8_739_,
    document0_3_.Locked as Locked739_,
    document0_4_.CreatedOn as CreatedOn754_,
    document0_4_.UpdatedOn as UpdatedOn754_,
    document0_4_.DeletedOn as DeletedOn754_,
    document0_4_.Deleted as Deleted754_,
    document0_4_.Active as Active754_,
    document0_4_.ActivatedOn as Activate7_754_,
    document0_4_.DeactivatedOn as Deactiva8_754_,
    document0_4_.Locked as Locked754_,
    document0_5_.CreatedOn as CreatedOn755_,
    document0_5_.UpdatedOn as UpdatedOn755_,
    document0_5_.DeletedOn as DeletedOn755_,
    document0_5_.Deleted as Deleted755_,
    document0_5_.Active as Active755_,
    document0_5_.ActivatedOn as Activate7_755_,
    document0_5_.DeactivatedOn as Deactiva8_755_,
    document0_5_.Locked as Locked755_,
    document0_6_.CreatedOn as CreatedOn759_,
    document0_6_.UpdatedOn as UpdatedOn759_,
    document0_6_.DeletedOn as DeletedOn759_,
    document0_6_.Deleted as Deleted759_,
    document0_6_.Active as Active759_,
    document0_6_.ActivatedOn as Activate7_759_,
    document0_6_.DeactivatedOn as Deactiva8_759_,
    document0_6_.Locked as Locked759_,
    document0_7_.CreatedOn as CreatedOn773_,
    document0_7_.UpdatedOn as UpdatedOn773_,
    document0_7_.DeletedOn as DeletedOn773_,
    document0_7_.Deleted as Deleted773_,
    document0_7_.Active as Active773_,
    document0_7_.ActivatedOn as Activate7_773_,
    document0_7_.DeactivatedOn as Deactiva8_773_,
    document0_7_.Locked as Locked773_,
    document0_8_.CreatedOn as CreatedOn774_,
    document0_8_.UpdatedOn as UpdatedOn774_,
    document0_8_.DeletedOn as DeletedOn774_,
    document0_8_.Deleted as Deleted774_,
    document0_8_.Active as Active774_,
    document0_8_.ActivatedOn as Activate7_774_,
    document0_8_.DeactivatedOn as Deactiva8_774_,
    document0_8_.Locked as Locked774_,
    document0_9_.CreatedOn as CreatedOn779_,
    document0_9_.UpdatedOn as UpdatedOn779_,
    document0_9_.DeletedOn as DeletedOn779_,
    document0_9_.Deleted as Deleted779_,
    document0_9_.Active as Active779_,
    document0_9_.ActivatedOn as Activate7_779_,
    document0_9_.DeactivatedOn as Deactiva8_779_,
    document0_9_.Locked as Locked779_,
    document0_10_.CreatedOn as CreatedOn780_,
    document0_10_.UpdatedOn as UpdatedOn780_,
    document0_10_.DeletedOn as DeletedOn780_,
    document0_10_.Deleted as Deleted780_,
    document0_10_.Active as Active780_,
    document0_10_.ActivatedOn as Activate7_780_,
    document0_10_.DeactivatedOn as Deactiva8_780_,
    document0_10_.Locked as Locked780_,
    document0_11_.CreatedOn as CreatedOn781_,
    document0_11_.UpdatedOn as UpdatedOn781_,
    document0_11_.DeletedOn as DeletedOn781_,
    document0_11_.Deleted as Deleted781_,
    document0_11_.Active as Active781_,
    document0_11_.ActivatedOn as Activate7_781_,
    document0_11_.DeactivatedOn as Deactiva8_781_,
    document0_11_.Locked as Locked781_,
    document0_11_.ExpiryDate as ExpiryDate781_,
    document0_11_.Number as Number781_,
    document0_11_.CreateUserID as CreateU12_781_,
    document0_11_.UpdateUserID as UpdateU13_781_,
    document0_12_.CreatedOn as CreatedOn784_,
    document0_12_.UpdatedOn as UpdatedOn784_,
    document0_12_.DeletedOn as DeletedOn784_,
    document0_12_.Deleted as Deleted784_,
    document0_12_.Active as Active784_,
    document0_12_.ActivatedOn as Activate7_784_,
    document0_12_.DeactivatedOn as Deactiva8_784_,
    document0_12_.Locked as Locked784_,
    document0_12_.CreateUserID as CreateU10_784_,
    document0_12_.UpdateUserID as UpdateU11_784_,
    document0_12_.SurveyID as SurveyID784_,
    document0_13_.CreatedOn as CreatedOn789_,
    document0_13_.UpdatedOn as UpdatedOn789_,
    document0_13_.DeletedOn as DeletedOn789_,
    document0_13_.Deleted as Deleted789_,
    document0_13_.Active as Active789_,
    document0_13_.ActivatedOn as Activate7_789_,
    document0_13_.DeactivatedOn as Deactiva8_789_,
    document0_13_.Locked as Locked789_,
    document0_14_.CreatedOn as CreatedOn790_,
    document0_14_.UpdatedOn as UpdatedOn790_,
    document0_14_.DeletedOn as DeletedOn790_,
    document0_14_.Deleted as Deleted790_,
    document0_14_.Active as Active790_,
    document0_14_.ActivatedOn as Activate7_790_,
    document0_14_.DeactivatedOn as Deactiva8_790_,
    document0_14_.Locked as Locked790_,
    document0_14_.aboriginal as aboriginal790_,
    document0_14_.disability as disability790_,
    document0_14_.minority as minority790_,
    document0_14_.refuse as refuse790_,
    document0_14_.CreateUserID as CreateU14_790_,
    document0_14_.UpdateUserID as UpdateU15_790_,
    document0_15_.CreatedOn as CreatedOn791_,
    document0_15_.UpdatedOn as UpdatedOn791_,
    document0_15_.DeletedOn as DeletedOn791_,
    document0_15_.Deleted as Deleted791_,
    document0_15_.Active as Active791_,
    document0_15_.ActivatedOn as Activate7_791_,
    document0_15_.DeactivatedOn as Deactiva8_791_,
    document0_15_.Locked as Locked791_,
    document0_15_.TypeOfTraining as TypeOfT10_791_,
    document0_15_.Location as Location791_,
    document0_15_.TrainerName as Trainer12_791_,
    document0_15_.[Result] as Result13_791_,
    document0_15_.TrainingDate as Trainin14_791_,
    document0_15_.ExpiryDate as ExpiryDate791_,
    document0_15_.CreateUserID as CreateU16_791_,
    document0_15_.UpdateUserID as UpdateU17_791_,
    document0_16_.CreatedOn as CreatedOn792_,
    document0_16_.UpdatedOn as UpdatedOn792_,
    document0_16_.DeletedOn as DeletedOn792_,
    document0_16_.Deleted as Deleted792_,
    document0_16_.Active as Active792_,
    document0_16_.ActivatedOn as Activate7_792_,
    document0_16_.DeactivatedOn as Deactiva8_792_,
    document0_16_.Locked as Locked792_,
    document0_16_.CreateUserID as CreateU10_792_,
    document0_16_.UpdateUserID as UpdateU11_792_,
    document0_17_.CreatedOn as CreatedOn793_,
    document0_17_.UpdatedOn as UpdatedOn793_,
    document0_17_.DeletedOn as DeletedOn793_,
    document0_17_.Deleted as Deleted793_,
    document0_17_.Active as Active793_,
    document0_17_.ActivatedOn as Activate7_793_,
    document0_17_.DeactivatedOn as Deactiva8_793_,
    document0_17_.Locked as Locked793_,
    document0_17_.Content as Content793_,
    document0_17_.CreateUserID as CreateU11_793_,
    document0_17_.UpdateUserID as UpdateU12_793_,
    document0_18_.CreatedOn as CreatedOn795_,
    document0_18_.UpdatedOn as UpdatedOn795_,
    document0_18_.DeletedOn as DeletedOn795_,
    document0_18_.Deleted as Deleted795_,
    document0_18_.Active as Active795_,
    document0_18_.ActivatedOn as Activate7_795_,
    document0_18_.DeactivatedOn as Deactiva8_795_,
    document0_18_.Locked as Locked795_,
    document0_19_.CreatedOn as CreatedOn800_,
    document0_19_.UpdatedOn as UpdatedOn800_,
    document0_19_.DeletedOn as DeletedOn800_,
    document0_19_.Deleted as Deleted800_,
    document0_19_.Active as Active800_,
    document0_19_.ActivatedOn as Activate7_800_,
    document0_19_.DeactivatedOn as Deactiva8_800_,
    document0_19_.Locked as Locked800_,
    document0_20_.CreatedOn as CreatedOn802_,
    document0_20_.UpdatedOn as UpdatedOn802_,
    document0_20_.DeletedOn as DeletedOn802_,
    document0_20_.Deleted as Deleted802_,
    document0_20_.Active as Active802_,
    document0_20_.ActivatedOn as Activate7_802_,
    document0_20_.DeactivatedOn as Deactiva8_802_,
    document0_20_.Locked as Locked802_,
    document0_20_.StartDate as StartDate802_,
    document0_20_.EndDate as EndDate802_,
    document0_21_.CreatedOn as CreatedOn807_,
    document0_21_.UpdatedOn as UpdatedOn807_,
    document0_21_.DeletedOn as DeletedOn807_,
    document0_21_.Deleted as Deleted807_,
    document0_21_.Active as Active807_,
    document0_21_.ActivatedOn as Activate7_807_,
    document0_21_.DeactivatedOn as Deactiva8_807_,
    document0_21_.Locked as Locked807_,
    document0_21_.CreateUserID as CreateU18_807_,
    document0_21_.UpdateUserID as UpdateU19_807_,
    document0_21_.EducationLevelTypeID as Educati21_807_,
    document0_22_.CreatedOn as CreatedOn808_,
    document0_22_.UpdatedOn as UpdatedOn808_,
    document0_22_.DeletedOn as DeletedOn808_,
    document0_22_.Deleted as Deleted808_,
    document0_22_.Active as Active808_,
    document0_22_.ActivatedOn as Activate7_808_,
    document0_22_.DeactivatedOn as Deactiva8_808_,
    document0_22_.Locked as Locked808_,
    document0_22_.CreateUserID as CreateU10_808_,
    document0_22_.UpdateUserID as UpdateU11_808_,
    document0_23_.CreatedOn as CreatedOn809_,
    document0_23_.UpdatedOn as UpdatedOn809_,
    document0_23_.DeletedOn as DeletedOn809_,
    document0_23_.Deleted as Deleted809_,
    document0_23_.Active as Active809_,
    document0_23_.ActivatedOn as Activate7_809_,
    document0_23_.DeactivatedOn as Deactiva8_809_,
    document0_23_.Locked as Locked809_,
    document0_24_.CreatedOn as CreatedOn810_,
    document0_24_.UpdatedOn as UpdatedOn810_,
    document0_24_.DeletedOn as DeletedOn810_,
    document0_24_.Deleted as Deleted810_,
    document0_24_.Active as Active810_,
    document0_24_.ActivatedOn as Activate7_810_,
    document0_24_.DeactivatedOn as Deactiva8_810_,
    document0_24_.Locked as Locked810_,
    document0_24_.CreateUserID as CreateU10_810_,
    document0_24_.UpdateUserID as UpdateU11_810_,
    document0_25_.CreatedOn as CreatedOn811_,
    document0_25_.UpdatedOn as UpdatedOn811_,
    document0_25_.DeletedOn as DeletedOn811_,
    document0_25_.Deleted as Deleted811_,
    document0_25_.Active as Active811_,
    document0_25_.ActivatedOn as Activate7_811_,
    document0_25_.DeactivatedOn as Deactiva8_811_,
    document0_25_.Locked as Locked811_,
    document0_26_.CreatedOn as CreatedOn815_,
    document0_26_.UpdatedOn as UpdatedOn815_,
    document0_26_.DeletedOn as DeletedOn815_,
    document0_26_.Deleted as Deleted815_,
    document0_26_.Active as Active815_,
    document0_26_.ActivatedOn as Activate7_815_,
    document0_26_.DeactivatedOn as Deactiva8_815_,
    document0_26_.Locked as Locked815_,
    document0_27_.CreatedOn as CreatedOn816_,
    document0_27_.UpdatedOn as UpdatedOn816_,
    document0_27_.DeletedOn as DeletedOn816_,
    document0_27_.Deleted as Deleted816_,
    document0_27_.Active as Active816_,
    document0_27_.ActivatedOn as Activate7_816_,
    document0_27_.DeactivatedOn as Deactiva8_816_,
    document0_27_.Locked as Locked816_,
    document0_27_.DateReceived as DateRec10_816_,
    document0_27_.DateIssued as DateIssued816_,
    document0_27_.CreateUserID as CreateU12_816_,
    document0_27_.UpdateUserID as UpdateU13_816_,
    document0_28_.CreatedOn as CreatedOn819_,
    document0_28_.UpdatedOn as UpdatedOn819_,
    document0_28_.DeletedOn as DeletedOn819_,
    document0_28_.Deleted as Deleted819_,
    document0_28_.Active as Active819_,
    document0_28_.ActivatedOn as Activate7_819_,
    document0_28_.DeactivatedOn as Deactiva8_819_,
    document0_28_.Locked as Locked819_,
    document0_28_.LicenceDocumentNumber as Licence10_819_,
    document0_28_.DemeritPoints as Demerit11_819_,
    document0_28_.MeritPoints as MeritPo12_819_,
    document0_28_.ExpiryDate as ExpiryDate819_,
    document0_28_.CreateUserID as CreateU14_819_,
    document0_28_.UpdateUserID as UpdateU15_819_,
    document0_28_.LicenceDocumentStatusTypeID as Licence16_819_,
    document0_28_.StateProvinceID as StatePr17_819_,
    document0_29_.CreatedOn as CreatedOn820_,
    document0_29_.UpdatedOn as UpdatedOn820_,
    document0_29_.DeletedOn as DeletedOn820_,
    document0_29_.Deleted as Deleted820_,
    document0_29_.Active as Active820_,
    document0_29_.ActivatedOn as Activate7_820_,
    document0_29_.DeactivatedOn as Deactiva8_820_,
    document0_29_.Locked as Locked820_,
    document0_29_.CreateUserID as CreateU10_820_,
    document0_29_.UpdateUserID as UpdateU11_820_,
    document0_30_.CreatedOn as CreatedOn821_,
    document0_30_.UpdatedOn as UpdatedOn821_,
    document0_30_.DeletedOn as DeletedOn821_,
    document0_30_.Deleted as Deleted821_,
    document0_30_.Active as Active821_,
    document0_30_.ActivatedOn as Activate7_821_,
    document0_30_.DeactivatedOn as Deactiva8_821_,
    document0_30_.Locked as Locked821_,
    document0_30_.ExpiryDate as ExpiryDate821_,
    document0_30_.LicenceNumber as Licence11_821_,
    document0_30_.CreateUserID as CreateU12_821_,
    document0_30_.UpdateUserID as UpdateU13_821_,
    document0_30_.StateProvinceID as StatePr14_821_,
    document0_31_.CreatedOn as CreatedOn822_,
    document0_31_.UpdatedOn as UpdatedOn822_,
    document0_31_.DeletedOn as DeletedOn822_,
    document0_31_.Deleted as Deleted822_,
    document0_31_.Active as Active822_,
    document0_31_.ActivatedOn as Activate7_822_,
    document0_31_.DeactivatedOn as Deactiva8_822_,
    document0_31_.Locked as Locked822_,
    document0_32_.CreatedOn as CreatedOn823_,
    document0_32_.UpdatedOn as UpdatedOn823_,
    document0_32_.DeletedOn as DeletedOn823_,
    document0_32_.Deleted as Deleted823_,
    document0_32_.Active as Active823_,
    document0_32_.ActivatedOn as Activate7_823_,
    document0_32_.DeactivatedOn as Deactiva8_823_,
    document0_32_.Locked as Locked823_,
    document0_33_.CreatedOn as CreatedOn824_,
    document0_33_.UpdatedOn as UpdatedOn824_,
    document0_33_.DeletedOn as DeletedOn824_,
    document0_33_.Deleted as Deleted824_,
    document0_33_.Active as Active824_,
    document0_33_.ActivatedOn as Activate7_824_,
    document0_33_.DeactivatedOn as Deactiva8_824_,
    document0_33_.Locked as Locked824_,
    document0_33_.CreateUserID as CreateU10_824_,
    document0_33_.UpdateUserID as UpdateU11_824_,
    document0_34_.CreatedOn as CreatedOn825_,
    document0_34_.UpdatedOn as UpdatedOn825_,
    document0_34_.DeletedOn as DeletedOn825_,
    document0_34_.Deleted as Deleted825_,
    document0_34_.Active as Active825_,
    document0_34_.ActivatedOn as Activate7_825_,
    document0_34_.DeactivatedOn as Deactiva8_825_,
    document0_34_.Locked as Locked825_,
    document0_35_.CreatedOn as CreatedOn826_,
    document0_35_.UpdatedOn as UpdatedOn826_,
    document0_35_.DeletedOn as DeletedOn826_,
    document0_35_.Deleted as Deleted826_,
    document0_35_.Active as Active826_,
    document0_35_.ActivatedOn as Activate7_826_,
    document0_35_.DeactivatedOn as Deactiva8_826_,
    document0_35_.Locked as Locked826_,
    document0_35_.ExpiryDate as ExpiryDate826_,
    document0_35_.CreateUserID as CreateU11_826_,
    document0_35_.UpdateUserID as UpdateU12_826_,
    document0_36_.CreatedOn as CreatedOn827_,
    document0_36_.UpdatedOn as UpdatedOn827_,
    document0_36_.DeletedOn as DeletedOn827_,
    document0_36_.Deleted as Deleted827_,
    document0_36_.Active as Active827_,
    document0_36_.ActivatedOn as Activate7_827_,
    document0_36_.DeactivatedOn as Deactiva8_827_,
    document0_36_.Locked as Locked827_,
    document0_36_.ExpiryDate as ExpiryDate827_,
    document0_36_.CreateUserID as CreateU11_827_,
    document0_36_.UpdateUserID as UpdateU12_827_,
    document0_37_.CreatedOn as CreatedOn829_,
    document0_37_.UpdatedOn as UpdatedOn829_,
    document0_37_.DeletedOn as DeletedOn829_,
    document0_37_.Deleted as Deleted829_,
    document0_37_.Active as Active829_,
    document0_37_.ActivatedOn as Activate7_829_,
    document0_37_.DeactivatedOn as Deactiva8_829_,
    document0_37_.Locked as Locked829_,
    document0_37_.CheckDate as CheckDate829_,
    document0_37_.CreateUserID as CreateU11_829_,
    document0_37_.UpdateUserID as UpdateU12_829_,
    document0_38_.CreatedOn as CreatedOn830_,
    document0_38_.UpdatedOn as UpdatedOn830_,
    document0_38_.DeletedOn as DeletedOn830_,
    document0_38_.Deleted as Deleted830_,
    document0_38_.Active as Active830_,
    document0_38_.ActivatedOn as Activate7_830_,
    document0_38_.DeactivatedOn as Deactiva8_830_,
    document0_38_.Locked as Locked830_,
    document0_39_.CreatedOn as CreatedOn831_,
    document0_39_.UpdatedOn as UpdatedOn831_,
    document0_39_.DeletedOn as DeletedOn831_,
    document0_39_.Deleted as Deleted831_,
    document0_39_.Active as Active831_,
    document0_39_.ActivatedOn as Activate7_831_,
    document0_39_.DeactivatedOn as Deactiva8_831_,
    document0_39_.Locked as Locked831_,
    document0_40_.CreatedOn as CreatedOn832_,
    document0_40_.UpdatedOn as UpdatedOn832_,
    document0_40_.DeletedOn as DeletedOn832_,
    document0_40_.Deleted as Deleted832_,
    document0_40_.Active as Active832_,
    document0_40_.ActivatedOn as Activate7_832_,
    document0_40_.DeactivatedOn as Deactiva8_832_,
    document0_40_.Locked as Locked832_,
    document0_41_.CreatedOn as CreatedOn833_,
    document0_41_.UpdatedOn as UpdatedOn833_,
    document0_41_.DeletedOn as DeletedOn833_,
    document0_41_.Deleted as Deleted833_,
    document0_41_.Active as Active833_,
    document0_41_.ActivatedOn as Activate7_833_,
    document0_41_.DeactivatedOn as Deactiva8_833_,
    document0_41_.Locked as Locked833_,
    document0_41_.CreateUserID as CreateU10_833_,
    document0_41_.UpdateUserID as UpdateU11_833_,
    document0_.Subtype as Subtype715_ 
from
    Document document0_ 
left outer join
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Answer 1

感谢@TabAlleman、@Ionic 等。这些评论帮助我意识到，正是执行计划的计算占用了如此多的资源。这个认识让我找到了this SO question询问在 SQL Server 2014 中需要很长时间才能生成的执行计划。

我应该提到我们使用的是 SQL Server 2014，因为事实证明该版本引入了一个积极的新查询优化器，该优化器对相关查询有问题。如果我将数据库兼容性设置为 SQL Server 2012，则立即生成执行计划。

我可能仍会在 SQL Connect 中记录一个错误，因为此查询可能代表需要研究的边缘情况。

谢谢大家。