"Incorrect prefix key" error during inplace 5.7 to 8.0 upgrade

[Christos Chatzaras]

I try to do inplace upgrade from 5.7 to 8.0. At the final step when I start mysql-server I see these on the logs. Any idea how to proceed or at least find which database causes this issue?

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2022-01-07T22:39:53.031251Z 1 [System] [MY-011012] [Server] Starting upgrade of data directory.
2022-01-07T22:39:53.031266Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2022-01-07T22:39:59.731094Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
2022-01-07T22:41:04.547365Z 2 [ERROR] [MY-013140] [Server] Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys
2022-01-07T22:41:04.560303Z 2 [ERROR] [MY-013140] [Server] Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys
2022-01-07T22:41:04.997305Z 2 [ERROR] [MY-013140] [Server] Too many key parts specified; max 1 parts allowed
2022-01-07T22:41:51.265067Z 0 [ERROR] [MY-010022] [Server] Failed to Populate DD tables.
2022-01-07T22:41:51.265192Z 0 [ERROR] [MY-010119] [Server] Aborting
2022-01-07T22:41:59.469949Z 0 [System] [MY-010910] [Server] /usr/local/libexec/mysqld: Shutdown complete (mysqld 8.0.27) Source distribution.