SQLite: Enable ef_compare for decimals

[lokalmatador]

Part of #19635

[dnfclas]

All CLA requirements met.

[lokalmatador]

@bricelam, so I went ahead and had a first look at the code (specifically your mentioned PR on datetime and the one on ef_mod) you and then just attempted to follow what I saw there, to somehow get an idea (monkey see, monkey do) of how ef_compare could work. The contents of this PR by no means provide a draft or anything close to that. But maybe they provide a basis for discussing the implementation.

What I wanted to ask before actually trying to work in an implementation

• how would I add my own tests for driving my implementation?
• is there some specification (or similar available) guiding test design?

I'll try to have a more thorough look at the code infrastructure next week, yet, any help/pointers would be greatly appreciated - thanks!

[bricelam]

It looks like we already have some tests in test/EFCore.Sqlite.FunctionalTests/BuiltInDataTypesSqliteTest.cs. The comparison is done on the client, but if you enable a server translation, they'll verify that the result is still correct.

[lokalmatador]

Thanks for the tips, I actually now got the tests running and see some errors. Gonna submit an updated over the weekend.

[smitpatel]

what is oracle!?

[AndriySvyryd]

oracle: a person or thing regarded as an infallible authority or guide on something.

[bricelam]

Kind of like a sentinel but non-arbitrary and with canonical semantics

[lokalmatador]

Exactly. The oracle predicts the expected result (which in this case is 0). But if desired, I'm happy to rename it to, e.g., expectedResult or sth similar.

[JonPSmith]

Hi @lokalmatador ,

Can I ask a question about what you are doing? I can't currently filter/order on a decimal in Sqlite database provider. Will your changes fix that?

[lokalmatador]

Hi @JonPSmith ,
I'm currently working of various items in this list. As mentioned by @bricelam (if I got it correctly) , OrderBy won't be implemented for SQLite, yet I can't elaborate on why. For filtering, for now I do not think it's planned, but again, @bricelam probably better knows about that. I eventually just contribute code 😄

[JonPSmith]

Hi @lokalmatador,

Thanks for the update, and for your help in moving EF Core forward. Great stuff. I was asking as I'm working on some docs, so now I know.