Molto semplicemente eseguendo (cambiando ovviamente dbname e tablename) questa query potete capire la codifica:
![](https://1.bp.blogspot.com/-ae_HIoLlG-8/XszszqL26pI/AAAAAAAACjI/WDYULzoxJNIsO-3VMlHfliqh32CwFfGOACK4BGAsYHg/s1200/Come%2Bcontrollare%2Bse%2Buna%2Btabella%2Bdi%2BMySQL%2Be%25CC%2580%2Bcodificata%2Bin%2BUTF8.png)
select c.character_set_name from information_schema.tables as t, information_schema.collation_character_set_applicability as c where c.collation_name = t.table_collation and t.table_schema = "dbname" and t.table_name = "tablename";
![](https://1.bp.blogspot.com/-O90UdQKxkq8/W7MXtHGHSBI/AAAAAAAAFGg/rfoJdu_JD4opeSNLpt_DotFI-5rWlqR6QCLcBGAs/s1600/Come%2Bcontrollare%2Bse%2Buna%2Btabella%2Be%25CC%2580%2Bcodificata%2Bin%2BUTF8.png)
Se vi rendete conto che non è in utf8, vi basta eseguire (prima fate un backup):
ALTER DATABASE databasename CHARACTER SET utf8 COLLATE utf8_unicode_ci; ALTER TABLE tablename CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
Altrimenti se la volete in utf8mb4:
ALTER TABLE tablename CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci; ALTER DATABASE databasename CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
Altri suggerimenti su come fare conversioni potete trovarne qui, oppure qui.