Comment 2 for bug 1906290

Thank you for taking the time to file a bug report.

Checking the attached logs I found this:

2020-11-30T17:51:13.420162Z 0 [ERROR] [MY-000067] [Server] unknown variable 'query_cache_limit=1M'.
2020-11-30T17:51:13.420930Z 0 [ERROR] [MY-010119] [Server] Aborting

From https://dev.mysql.com/doc/refman/8.0/en/added-deprecated-removed.html, we can see that the config option query_cache_limit was removed in 8.0.3:
"""
 query_cache_limit: Do not cache results that are bigger than this. Removed in MySQL 8.0.3.
"""

If you remove this option from your config file mysql will work again.

Since it seems likely to me that this is a local configuration problem,
rather than a bug in Ubuntu, I am marking this bug as 'Incomplete'.

However, if you believe that this is really a bug in Ubuntu, then we would
be grateful if you would provide a more complete description of the problem
with steps to reproduce, explain why you believe this is a bug in Ubuntu
rather than a problem specific to your system, and then change the bug
status back to "New".

For local configuration issues, you can find assistance here:
http://www.ubuntu.com/support/community