MySQL 8.0

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select version();


version()


8.0.36


CREATE TABLE sample ( data text DEFAULT NULL ) 
 ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci; 
 INSERT INTO sample VALUES (
 'Mr. Geoffrey H. Yost, Oï¿½Melveny & Myers LLP')
 ,('Valero Refining Company ï¿½ California')
 ,('El Paso Merchant Energy ï¿½ Petroleum Company')
 ,('PapÃ© Group/IFCO')
 ,('Huntonsï¿½ SureCrop Farm Svc Inc dba SureCrop Farm')
 ,('developed, manufactured, marketed, tested, and sold the electronic diesel control that allowed Mercedes to manipulate emissions controls and that Bosch marketed ¢€š¬Ã…¡¬ÃƒÆ’‚¬¦¡€š¬Ã…¡¬Ãƒ€ ‚¬„¢‚¬Å¡¬¦¢€š¬Ã…¡¬ÃƒÆ’‚¬¦€š¬Ã…€œClean Diesel¢€š¬Ã…¡¬ÃƒÆ’‚¬¦¡€š¬Ã…¡¬€š¬Ã…¡<9d> to the public.'); 

Records: 6  Duplicates: 0  Warnings: 0


-- Because I do not like selecting text with weird characters:
alter table sample add id INT AUTO_INCREMENT PRIMARY KEY;

Records: 0  Duplicates: 0  Warnings: 0


select 
   id, 
   data, 
   convert(cast(convert(data using  latin1) as binary) using utf8mb4) L 
from sample 
where id=4;


id
data
L


4
PapÃ© Group/IFCO
Papé Group/IFCO


select id, data, convert(cast(convert(data using  latin1) as binary) using utf8mb4) as d2 
from sample 
where data collate utf8mb4_0900_ai_ci != convert(cast(convert(data using  latin1) as binary) using utf8mb4) and id between 5 and 5;
show warnings;



id
data
d2


5
Huntonsï¿½ SureCrop Farm Svc Inc dba SureCrop Farm
Huntons� SureCrop Farm Svc Inc dba SureCrop Farm




Level
Code
Message


select id, data, convert(cast(convert(data using  latin1) as binary) using utf8mb4) as d2 
from sample 
where data collate utf8mb4_0900_ai_ci != convert(cast(convert(data using  latin1) as binary) using utf8mb4) and id >= 5;
show warnings;


id
data
d2


5
Huntonsï¿½ SureCrop Farm Svc Inc dba SureCrop Farm
Huntons� SureCrop Farm Svc Inc dba SureCrop Farm




Level
Code
Message


Warning
1300
Invalid utf8mb4 character string: 'A2809A'