The full syntax of CONNECTION blocks is as follows

CONNECTION'CONNECTION_NAME' [EXTERN'CONNECTION_FILE'] (DRIVER ='CONNECTION_DRIVER_NAME' [,CONNECTION_OPTIONS])

A connection represents a data source and/or a data sink that can be queried against or that rows can be sent to.

Connection options are driver-specific. Currently supported drivers are:

• mssql: Microsoft SQL Server database (Source/Sink)
• sqlite3: SQLite 3 database (Source/Sink)
• postgres: Postgres database (Source/Sink)
• excel: Microsoft Excel 2010+ (Source/Sink)
• mandrill: Mandrill email API (Sink only)
• http: an API served over HTTP (Source only)