Windows
1) Locate the my.ini, which store in the MySQL installation folder.
For Example,
C:\Program Files\MySQL\MySQL Server 5.1\my.ini
2) Open the “my.ini” with our favor text editor.
#Path to installation directory. All paths are usually resolved relative to this.
basedir="C:/Program Files/MySQL/MySQL Server 5.1/"
#Path to the database root
datadir="C:\ProgramData\MySQL\MySQL Server 5.1\data"
Find the “datadir”, this is the where does MySQL stored the data in Windows
now check
C:\ProgramData\MySQL\MySQL Server 5.1\data
This is Hidden file so go to view >> show hidden folder.