EF Core不断抱怨不存在的索引

如何解决EF Core不断抱怨不存在的索引

在运行时，我有一堆日志从EF Core抱怨，看起来像这样：

[10:56:14 DBG] The index {'InvoiceId'} was not created on entity type 'CompleteCase' as the properties are already covered by the index {'InvoiceId','Code'}.
[10:56:14 DBG] The index {'ReportPeriodId'} was not created on entity type 'FixedBill' as the properties are already covered by the index {'ReportPeriodId','MedCompanyTypeId','FixedBillTypeId'}.
[10:56:14 DBG] The index {'CasePeriodId'} was not created on entity type 'Invoice' as the properties are already covered by the index {'CasePeriodId','ReportPeriodId','MedCompanyTypeId'}.
[10:56:14 DBG] The index {'InvoiceId'} was not created on entity type 'InvoiceFixedBillMap' as the properties are already covered by the index {'InvoiceId','FixedBillId'}.
[10:56:14 DBG] The index {'MedCompanyDepartmentTypeId'} was not created on entity type 'MedCompanyDepartmentDoctorMap' as the properties are already covered by the index {'MedCompanyDepartmentTypeId','MedCompanyDoctorTypeId','DoctorSpecialtyTypeId','StartDate','EndDate'}.
[10:56:14 DBG] The index {'VMPMethodTypeId'} was not created on entity type 'VMPMethodMKBMap' as the properties are already covered by the index {'VMPMethodTypeId','MKBTypeId'}.
[10:56:14 DBG] The index {'KSGBaseRateTypeId'} was not created on entity type 'KSGBaseRate' as the properties are already covered by the index {'KSGBaseRateTypeId','EndDate'}.
[10:56:14 DBG] The index {'KSGTypeId'} was not created on entity type 'KsgindexRate' as the properties are already covered by the index {'KSGTypeId','KsgindexTypeId','EndDate'}.
[10:56:14 DBG] The index {'MedCompanyTypeId'} was not created on entity type 'MedCompanyKsgindexRate' as the properties are already covered by the index {'MedCompanyTypeId','MedCompanyUnitTypeId','MedCompanyDepartmentTypeId','UMPTypeId','EndDate'}.
[10:56:14 DBG] The index {'UserId'} was not created on entity type 'UserRole' as the properties are already covered by the index {'UserId','RoleId'}.
[10:56:14 DBG] The index {'UserId'} was not created on entity type 'IdentityUserToken<Guid>' as the properties are already covered by the index {'UserId','LoginProvider','Name'}.

我可以看到它们的原因-因为有使用这些列的复合索引，它们使单独的索引变得无用。这些列都是外键，EF Core在迁移过程中会自动创建。

但是这些索引实际上都不存在于迁移中或数据库本身中（代码优先）。我已经仔细检查过了。甚至删除了所有迁移，并从头开始创建了它们-什么都没有。但是在运行时，我每次都会得到这些。

可以安全忽略还是应该从我这边采取一些行动？

P.S。使用sql Server作为数据库提供程序在3.1.8上进行了测试。

解决方法

但是这些索引实际上都不存在于迁移中或数据库本身中（代码优先）。

当然没有，您在这里看到的只是一个警告，告诉您某些索引已从模型中删除（忽略）。可能令人困惑的部分是您没有明确请求此类索引，正如您所说，它们是由EF自动创建的（并且btw不能从外部删除），因此EF Core不会警告您。

但这就是它。不为正导致另一个索引的列生成索引是完全可以的。您可以放心地忽略它，并通过在OnConfiguring覆盖中添加以下内容来抑制它：

optionsBuilder.ConfigureWarnings(warnings => warnings
    .Ignore(CoreEventId.RedundantIndexRemoved);