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dbConnect() returns an S4 object that inherits from DBIConnection. This object is used to communicate with the database engine.

A format() method is defined for the connection object. It returns a string that consists of a single line of text.


DBI recommends using the following argument names for authentication parameters, with NULL default:

  • user for the user name (default: current user)

  • password for the password

  • host for the host name (default: local connection)

  • port for the port number (default: local connection)

  • dbname for the name of the database on the host, or the database file name

The defaults should provide reasonable behavior, in particular a local connection for host = NULL. For some DBMS (e.g., PostgreSQL), this is different to a TCP/IP connection to localhost.

In addition, DBI supports the bigint argument that governs how 64-bit integer data is returned. The following values are supported:

  • "integer": always return as integer, silently overflow

  • "numeric": always return as numeric, silently round

  • "character": always return the decimal representation as character

  • "integer64": return as a data type that can be coerced using as.integer() (with warning on overflow), as.numeric() and as.character()

See also