Very well written! Thanks. The only thing I'm missing is about scalability/clustering?
Yes, I missed that too. But there are plent of other places covering this issue - even here, maybe.
Where I'm working right now we are starting a new version from our main product, which includes studying another RDB that isn't MySQL/Maria, mostly because we have some issues with some data types (like the UUID field).
We also had a problem with the replication/scale of the db, however, this was more of a bad infrastructure design then a MySQL/Maria problem.
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