Each database is configured using a DB declaration.
The generalised form is
DB databasename [ Configuration options ]
The configuration options are tag/value pairs and must contain at least a description of the access method (using method: or one or more of methodsingle:, methodquery: and methodall:) and a description of the original format of the sequences (using format:).
In addition to these tags there will be other tags that are needed for particular methods and other tags that are optional.