OptionalParent is not so optional about fluent HOT 2 CLOSED

I think this is expected behaviour. Fluent makes no guarantees about how eager loading works (we would like to use joins where possible in the future for example) and we can change the implementations under the hood. There are a lot of assumptions in Fluent about constraints as well so using an @OptionalParent with a ID that doesn't exist (instead of it being nil - that's your issue correct?) would break some of Fluent's internals.

You're probably best off using an @OptionalField instead to hold the ID and doing the lookups yourself, including handling if that ID is not valid

from fluent.

It sounds essentially as if you're hoping to get the effect of a left outer join, while the Fluent relation properties are designed to provide the effect of an inner join.

If you want this behavior, you can copy the contents of OptionalParent.swift into a new file in your project, rename the wrapper (maybe something like @UncheckedOptionalParent), and replace the logic that throws an error with your preferred outcome. This being said, Fluent does not officially support third-party packages providing custom property wrappers, so I can't promise that doing this will continue to work on an ongoing basis. (Although, I do use several custom wrappers in external projects myself, so odds are I won't break the ability to do so too badly 😅.)

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