Hi ! Hi Vineet,
At present, I am using MySQL noinstall version (which doesn't require ANY installation). Just copy & paste the folder & start.
Is there any way to use MariaDB without installing? (Maybe replace MySQL folder containing the binaries with MariaDB folder? Yes , and yes . Caveat : If you're going to replace MySQL, don't copy over the 'data' folder from the zip, it would remove existing users and stored procedures since it replaces mysql.user and mysql.proc tables with fresh empty onces.
If yes, from where to get the noinstall folder for MariaDB?)
From downloads.mariadb.org For example, for the latest 5.5 version https://downloads.mariadb.org/mariadb/5.5.28a/ has 2 ZIPs , for 32 or 64 bit (because you say "folder", rather than "directory", I assume you're looking for Windows versions)