first of all you can save your accounts and charecter tables to upload again in the future if you need to. The way you do this is export the tables to excell which is easy, simply go intothe accounts table for instance then right click on any value and click export grid rows.
Secondly the database may not be compatible. I wouldn't recommend that you keep "up to date" on the database, but thats just me, I run a classic server though. What may have happened is the values may be different, like there may be an extra row added to the items or skill caps table or something like that. Hopefully a dev will see this and give you better advice but if it was me I would save the account and charecter tables and drop the db and add the new db then re-add your old account and charecter tables to the new database and don't update the database again
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