Clarify how EF uses indexes (i.e. currently only for update ordering)

[smcga]

I understand that when using migrations, indexes defined in OnModelCreating will be created in the database.

I have an existing database, with indexes already set up, and was wondering if there is a benefit to defining these indexes in my DbContext? Does EFCore use these index definitions to influence how it builds queries, or does defining an existing index have no effect?

Thanks

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Document Details

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• ID: f85ea32c-8d23-d61d-6036-cd772e3e95d9
• Version Independent ID: 25dd8ac4-2521-5200-0ddf-63ac8c83787a
• Content: Indexes - EF Core
• Content Source: entity-framework/core/modeling/indexes.md
• Product: entity-framework
• Technology: entity-framework-core
• GitHub Login: @rowanmiller
• Microsoft Alias: divega

[smcga]

I found an answer for this on SO - https://stackoverflow.com/questions/54299018/what-is-the-benefit-of-adding-hasindex-in-your-mappings-on-a-dbfirst-scenari

tl;dr - If you are not updating the DB with migrations, this does nothing.

[offirpeer]

If I created an index in my DB, how can I tell EF to use it when fetching the data?
https://stackoverflow.com/questions/62881671/ef-core-not-fetching-data-from-table-based-on-its-clustered-index