Introduction to MariaDB

MariaDB is an open-source relational database management system (RDBMS) that has become popular amongst the coders due to its robust features, performance, and compatibility with MySQL. 

The foundation for MariaDB was laid with the birth of MySQL in early 1990s by Michael Widenius and David Axmark. MySQL's simplicity, speed, and open-source nature helped it to swiftly rise to the top of the database management systems world wide. However, after the acquisition of MySQL by Oracle Corporation in the year 2009, technology enthusiasts started showing concerns about MySQL and thus MariaDB was developed. 

The idea behind developing MariaDB was to maintain the compatibility of MySQL while providing new features and enhancements to the developers. In 2010, the very first MariaDB version 1.5 was introduced to the world, which is also regarded as its first stable version. Since then, MariaDB has developed further, receiving frequent updates and seeing the addition of additional functionalities.

Key Features of MariaDB

1. Compatibility: MariaDB is highly compatible with MySQL, making it easy for users to migrate from MySQL to MariaDB without any major issues. MariaDB also supports the same database engines, APIs, and commands as MySQL.

2. Performance: MariaDB offers excellent performance, with optimizations for both read and write operations. It includes features such as the Aria storage engine for faster writes and the MariaDB ColumnStore for efficient analytical queries. MariaDB also supports parallel replication, which can significantly improve the performance of database replication.

3. Security: Mariadb software comes with additional security features that help in protecting your data, such as, SSL/TLS encryption, authentication plugins, and role-based access control (RBAC). Database and  table encryption are some of the other security features in MariaDB that ensure data is secure at rest and in transit. 

4. High Availability: MariaDB includes features to ensure high availability of your database, such as master-slave replication, multi-master replication, and automatic failover. These features help to minimize downtime and ensure that the database remains accessible even in the event of a failure.

5. Scalability: MariaDB is a highly scalable software that easily scalability for your database as your application grows. MariaDB supports sharding, which allows you to partition your data across multiple servers, as well as clustering, which allows you to create a cluster of MariaDB servers for improved performance and availability.

Architecture of MariaDB

MariaDB follows a client-server architecture, where the MariaDB server handles database queries from clients and manages the storage and retrieval of data.The MariaDB server consists of the following key components:

1. SQL Layer: The SQL layer of MariaDB is responsible for parsing and executing SQL queries. It includes components such as the query optimizer, which is responsible for optimizing query execution plans, and the query cache, which caches frequently executed queries to improve performance.

2. Storage Engines: MariaDB supports multiple storage engines, each with its own strengths and weaknesses. InnoDB is the most commonly used storage engine for MariaDB, which ensures high performance transaction processing. Other storage engines supported by MariaDB include Aria, MyISAM, and TokuDB, each of which is suited to different types of workloads.

3. Connection Handlers: The connection handlers in MariaDB are responsible for managing client connections to the server. Authentication, result retrieval and query execution are some of the tasks handled by them to ensure timely and efficient resolution of clients requests. 

4. Pluggable Authentication: MariaDB supports pluggable authentication, allowing use of external authentication mechanisms such as LDAP or PAM. This provides flexibility in how user authentication is managed and allows integration of MariaDB with existing authentication infrastructure.