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kotlinlang

Hi!
What is the best practice of using `data class` as `Entity` ?

don't, just read czar tutorial (official spring boot kotlin tutorial) a couple of posts above

data classes are not very suitable for JPA Entities (I'm inferring JPA here, since you haven't specified that).
E.g. see here: <https://kotlinexpertise.com/hibernate-with-kotlin-spring-boot/>
If you know what `data class` does and then read this guide, you'll see how data classes are not the best idea for entities.

yeap, so i'm considering to move all entities to regular class

Regular classes with `var` properties, `val` is not a good fit with JPA sadly.

looks like we still need to use Lombok :disappointed:

Use jooq instead of JPA, and avoid most issues.
Sure you have to write queries, but if some performance problem comes up, it's more easy to understand and debug, and it's also more easy to understand than knowing everything hibernate does under the hood, which eventually you will have to know if the project is long enough.