MariaDB versus MySQL - Compatibility
MariaDB is a binary drop in replacement for MySQL
For all practical purposes, MariaDB is a binary drop in replacement of the same MySQL version (for example MySQL 5.1 -> MariaDB 5.1, MariaDB 5.2 & MariaDB 5.3 are compatible. MySQL 5.5 will be compatible with MariaDB 5.5). What this means is that:
Data and table definition files (.frm) files are binary compatible.
All client APIs, protocols and structs are identical.
All filenames, binaries, paths, ports, sockets, and etc… should be the same.
All MySQL connectors (PHP, Perl, Python, Java, .NET, MyODBC, Ruby, MySQL C connector etc) work unchanged with MariaDB.
There are some installation issues with PHP5 that you should be aware of (a bug in how the old PHP5 client checks library compatibility).
The mysql-client package also works with MariaDB server.
The shared client library is binary compatible with MySQL’s client library.
This means that for most cases, you can just uninstall MySQL and install MariaDB and you are good to go. (No need to convert any datafiles if you use same main version, like 5.1).
Reference : https://kb.askmonty.org/
