Would it be possible to have a API for another database with its own topics, posts, search and integrate that into Discourse so I can use Discourse as a front end and that as an backend?

No. Think about import your data.

Is it possible to import 500gb+? Or is there a size limit

Интеграция существующей базы данных с Discourse

Falco (Falco) 17.Июль.2023 22:21:12 5

Нет, ограничения по размеру нет.

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