How to remove duplicate fields in mysql table

Mysql method to remove duplicate fields in the table: [delete deletion condition in (select unique identification column from table (extract duplicates) rename table))]. The deduplication operation in mysql generally requires multi-level statement nesting.

MySQL is a relational database management system developed by the Swedish MySQL AB company and is currently a product of Oracle. MySQL is one of the most popular relational database management systems. In terms of WEB applications, MySQL is the best RDBMS (Relational Database Management System) application software.

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Problem found?

The same data appears multiple times in the same table. My requirement is to delete redundant data but keep one of them.
Define the table name table_a, determine the only two fields c_1, c_2, and the irrelevant field data
The original data in the table is as follows

Delete statement:

DELETE FROM table_a 
WHERE id IN 
(SELECT id FROM 
(
SELECT id FROM table_a GROUP BY c_1,c_2 HAVING count(*) > 1
)e
);

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