我正在使用Linq-To-Entities进行查询,该查询仅返回947行但需要18秒才能运行.我已经做了一个“ToTraceString”来获取底层的sql并直接在数据库上运行相同的东西并获得相同的时间.

我使用了调优顾问并创建了几个索引,但影响不大.

查看查询执行计划有几个嵌套循环占95％的时间,但这些已经在索引上工作了？

有没有人有任何关于如何强制进行EF查询优化的想法？

编辑：提供其他信息

三个表的基本ER图如下：

People >----People_Event_Link ----< Events

P_ID P_ID E_ID

E_ID

我正在运行的linq旨在为特定Person获取所有事件(使用P_ID)：

var query = from ev in genesisContext.Events

join pe in genesisContext.People_Event_Link

on ev equals pe.Event

where pe.P_ID == key

select ev;

return query;

这是生成的SQL(深呼吸！)：

SELECT

1 AS [C1],

[Extent1].[E_ID] AS [E_ID],

[Extent1].[E_START_DATE] AS [E_START_DATE],

[Extent1].[E_END_DATE] AS [E_END_DATE],

[Extent1].[E_COMMENTS] AS [E_COMMENTS],

[Extent1].[E_DATE_ADDED] AS [E_DATE_ADDED],

[Extent1].[E_RECORDED_BY] AS [E_RECORDED_BY],

[Extent1].[E_DATE_UPDATED] AS [E_DATE_UPDATED],

[Extent1].[E_UPDATED_BY] AS [E_UPDATED_BY],

[Extent1].[ET_ID] AS [ET_ID],

[Extent1].[L_ID] AS [L_ID]

FROM [dbo].[Events] AS [Extent1]

INNER JOIN [dbo].[People_Event_Link] AS [Extent2] ON EXISTS (SELECT

1 AS [C1]

FROM ( SELECT 1 AS X ) AS [SingleRowTable1]

LEFT OUTER JOIN (SELECT

[Extent3].[E_ID] AS [E_ID]

FROM [dbo].[Events] AS [Extent3]

WHERE [Extent2].[E_ID] = [Extent3].[E_ID] ) AS [Project1] ON 1 = 1

LEFT OUTER JOIN (SELECT

[Extent4].[E_ID] AS [E_ID]

FROM [dbo].[Events] AS [Extent4]

WHERE [Extent2].[E_ID] = [Extent4].[E_ID] ) AS [Project2] ON 1 = 1

WHERE ([Extent1].[E_ID] = [Project1].[E_ID]) OR (([Extent1].[E_ID] IS NULL) AND ([Project2].[E_ID] IS NULL))

)

WHERE [Extent2].[P_ID] = 291