Mysql table size is 270 Gb but lib folder showing 810 GB can anyone guide me which files needs to be deleted

Question

Im using below query to calculate database tables size its showing 270 gb but when i go to linux server lib folder where i have installed my database in that server size is 810 gb. kindly guide me which files taking size and how i can resolve this issue. Query :

SELECT  (SUM(  ROUND(((data_length + index_length) / 1024 / 1024 ) )  ) /1024 )  AS gb
1024), 2) `Size in MB`
FROM information_schema.TABLES
ORDER BY (data_length + index_length) DESC
LIMIT 100;