Have you recently encountered the MySQL error Unknown Collation: utf8mb4_0900_ai_ci? That's because the databases' character sets are incompatible. To find the solution, read this blog post all the way through.
I recently used MySQL to manually import a database to a new server. Everything was going well... till 'utf8mb4 0900 ai ci' (unknown collation) displayed on my screen.
I looked deeper to discover the true problem and discovered that the new database's collation was different from the old one. I'll explain the approach I took to resolve this problem in this post. But first, let's clarify what "Collation" in MySQL means.
For the solution to this error, visit: https://meetanshi.com/blog/error-1273-unknown-collation-utf8mb4-0900-ai-ci-in-mysql/