Check size and location of data files or tablespaces present in MySQL or MariaDB

Check innodb_file_per_table parameter.
innodb_file_per_table=ON, InnoDB uses one tablespace file per table.
innodb_file_per_table=OFF, InnoDB stores all tables in the InnoDB system tablespace.

show variables like 'innodb_file_per_table'

Check the location of datafile/tablespace present in MySQL or MariaDB:

-- On MariaDB
show variables like 'datadir'
Variable_name|Value                              |
-------------+-----------------------------------+
datadir      |C:\Program Files\MariaDB 10.6\data\|

--On MySQL
show variables like 'datadir'
Variable_name|Value                                      |
-------------+-------------------------------------------+
datadir      |C:\ProgramData\MySQL\MySQL Server 8.0\Data\|

Check files and tablespace for MySQL:

select * from information_schema.FILES;

Check files and tablespace detail for MariaDB:

select * from information_schema.INNODB_SYS_TABLESPACES;