Open source databases are those databases who have an open source code i.e anyone may view the code, study it or even modify it. Open source databases could be relational (SQL) or non relational (NoSQL).
It is quite expensive to create and maintain a database for any company. A huge chunk of the total software expenditure is used to handle databases. So, it is feasible to switch to low cost open source databases. This saves companies a lot of money in the long run.
There many different open source databases in the market. All of them have their own pros and cons. A decision to use a open source database depends on personal requirements.
Some examples of open source databases are −
This is the world’s most successful open source database. A free community edition of MySQL is available but it was acquired by Oracle in 2010 and now Oracle charges for service.
This is a replacement of MySQL and intended to remain free unlike MySQL. MariaDB has a high compatibility with MySQL and its structure matches with MySQL API’s and commands.
This is an object relational database management system. PostgresSQL is more robust and has a better performance than MySQL. It is also known for its reliability and data integrity.
This is build on PostgresSQL but has extra functionality. It is available from Splendid data on a subscription basis.
This is also based on PostgresSQL but has extra features and tools such as performance, security and manageability enhancements.
This is a free open source NoSQL database program.It provides document validation, encrypted storage engine etc. MongoDB is used primarily in mobile apps etc.