How to remove accent values in MySQL

The UPDATE must be performed for each letter to be replaced, corresponding to the desired column:

UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Š','S');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'š','s');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ð','Dj');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ž','Z');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ž','z');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'À','A');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Á','A');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Â','A');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ã','A');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ä','A');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Å','A');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Æ','A');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ç','C');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'È','E');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'É','E');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ê','E');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ë','E');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ì','I');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Í','I');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Î','I');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ï','I');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ñ','N');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ò','O');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ó','O');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ô','O');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Õ','O');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ö','O');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ø','O');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ù','U');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ú','U');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Û','U');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ü','U');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ý','Y');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Þ','B');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ß','Ss');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'à','a');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'á','a');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'â','a');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ã','a');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ä','a');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'å','a');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'æ','a');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ç','c');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'è','e');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'é','e');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ê','e');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ë','e');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ì','i');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'í','i');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'î','i');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ï','i');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ð','o');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ñ','n');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ò','o');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ó','o');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ô','o');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'õ','o');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ö','o');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ø','o');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ù','u');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ú','u');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'û','u');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ý','y');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ý','y');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'þ','b');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ÿ','y');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ƒ','f');

UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ě','e');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ž','z');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'š','s');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'č','c');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ř','r');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ď','d');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ť','t');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ň','n');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'ů','u');

UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ě','E');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ž','Z');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Š','S');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Č','C');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ř','R');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ď','D');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ť','T');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ň','N');
UPDATE TABLE_NAME SET COLUMN = REPLACE(COLUMN,'Ů','U');

The answer above already helps you a lot, but if you have a database with many tables, you will have to do this manually, which honestly is a lot of work.

Always before you start deploying a MySQL database, try using the tool offered on the site itself: the MySQL Workbench . With it you can create diagrams and define the general encode of the database (which will cause your tables to inherit the encoding), so always try to use uft8_general_ci → utf-8 .