我有一个删除语句,它违反了我的一个核心应用程序表。 delete语句使用表的主键,但仍然需要大约30秒。据我所知,执行计划需要在其他表中执行12次检查,其中此表在执行删除之前是FK。我需要帮助阅读和理解这个执行计划,才能真正知道我能做些什么来解决这个问题。我猜测某些索引搜索或聚簇索引扫描需要调整。
StmtText --------------------------------------------- delete from Clean where CleanId = 17526195 (1 row(s) affected) StmtText -------- |--Assert(WHERE:(CASE WHEN NOT [Expr1042] IS NULL THEN (0) ELSE CASE WHEN NOT [Expr1043] IS NULL THEN (1) ELSE CASE WHEN NOT [Expr1044] IS NULL THEN (2) ELSE CASE WHEN NOT [Expr1045] IS NULL THEN (3) ELSE CASE WHEN NOT [Expr1046] IS NULL THEN (4) ELSE CA |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1053] = [PROBE VALUE])) |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1052] = [PROBE VALUE])) | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1051] = [PROBE VALUE])) | | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1050] = [PROBE VALUE])) | | | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1049] = [PROBE VALUE])) | | | | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1048] = [PROBE VALUE])) | | | | | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1047] = [PROBE VALUE])) | | | | | | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1046] = [PROBE VALUE])) | | | | | | | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1045] = [PROBE VALUE])) | | | | | | | | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1044] = [PROBE VALUE])) | | | | | | | | | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1043] = [PROBE VALUE])) | | | | | | | | | | |--Nested Loops(Left Semi Join, OUTER REFERENCES:([TcaNetMigrated].[dbo].[Clean].[CleanId]), DEFINE:([Expr1042] = [PROBE VALUE])) | | | | | | | | | | | |--Clustered Index Delete(OBJECT:([TcaNetMigrated].[dbo].[Clean].[PK_Clean]), OBJECT:([TcaNetMigrated].[dbo].[Clean].[_IX_Clean_CustomerID_CleanID]), OBJECT:([TcaNetMigrated].[dbo].[Clean]. | | | | | | | | | | | |--Index Seek(OBJECT:([TcaNetMigrated].[dbo].[Breakage].[IX_UniqueCleanId]), SEEK:([TcaNetMigrated].[dbo].[Breakage].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId]) ORDERED FORWARD) | | | | | | | | | | |--Index Seek(OBJECT:([TcaNetMigrated].[dbo].[Cancellation].[IX_UniqueCleanId]), SEEK:([TcaNetMigrated].[dbo].[Cancellation].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId]) ORDERED FORWARD) | | | | | | | | | |--Clustered Index Seek(OBJECT:([TcaNetMigrated].[dbo].[CleanEmployee].[PK_CleanEmployee]), SEEK:([TcaNetMigrated].[dbo].[CleanEmployee].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId]) ORDERED FO | | | | | | | | |--Index Seek(OBJECT:([TcaNetMigrated].[dbo].[CleanTransaction].[IX_UniqueCleanId]), SEEK:([TcaNetMigrated].[dbo].[CleanTransaction].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId]) ORDERED FORWARD) | | | | | | | |--Index Seek(OBJECT:([TcaNetMigrated].[dbo].[Complaint].[IX_UniqueCleanId]), SEEK:([TcaNetMigrated].[dbo].[Complaint].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId]) ORDERED FORWARD) | | | | | | |--Index Seek(OBJECT:([TcaNetMigrated].[dbo].[Complaint].[IX_Complaint_RedoCleanId]), SEEK:([TcaNetMigrated].[dbo].[Complaint].[RedoCleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId]) ORDERED FORWARD) | | | | | |--Index Seek(OBJECT:([TcaNetMigrated].[dbo].[GreatJob].[IX_UniqueCleanId]), SEEK:([TcaNetMigrated].[dbo].[GreatJob].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId]) ORDERED FORWARD) | | | | |--Index Seek(OBJECT:([TcaNetMigrated].[dbo].[Inspection].[IX_Inspection_CleanId_InspectionId]), SEEK:([TcaNetMigrated].[dbo].[Inspection].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId]) ORDERED FORWARD) | | | |--Clustered Index Scan(OBJECT:([TcaNetMigrated].[dbo].[FranchiseCall].[PK_FranchiseCalls]), WHERE:([TcaNetMigrated].[dbo].[FranchiseCall].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId])) | | |--Clustered Index Scan(OBJECT:([TcaNetMigrated].[dbo].[IVRLog].[PK_IVRLog]), WHERE:([TcaNetMigrated].[dbo].[IVRLog].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId])) | |--Index Seek(OBJECT:([TcaNetMigrated].[dbo].[Lockout].[IX_UniqueCleanId]), SEEK:([TcaNetMigrated].[dbo].[Lockout].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId]) ORDERED FORWARD) |--Clustered Index Scan(OBJECT:([TcaNetMigrated].[dbo].[ManualUpdateTime].[PK_ManualUpdateTimes]), WHERE:([TcaNetMigrated].[dbo].[ManualUpdateTime].[CleanId]=[TcaNetMigrated].[dbo].[Clean].[CleanId])) (26 row(s) affected)
答案 0 :(得分:7)
确保在其他表中的FK上有索引。
答案 1 :(得分:0)
在执行计划中,哪一步占据了多数时间?您还可以使用“Set Statistics IO ON”重新运行删除操作,并查看哪个表/索引具有最高的logica读数。这两位数据将是您需要注意的地方的有用提示。
答案 2 :(得分:0)
您确定此表或其他相关表中没有触发器吗?