Before any connection to a database can be made by Mergeant, it needs to be declared. The system maintains a list of connections, some global to all the users, and some local to a given user. The connections are identified by a unique identifier and each connection uses a database driver ("database provider") to access a specific database type (MySQL, PostgreSQL, Oracle, etc). Apart from choosing a database driver, each connection needs some information about where the database is located (on which machine), which database to connect to (in case a server handles more than one database), what user name and password to use, and various other information dependant on the database driver.