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1.1 Database Connections

(connection? x)  boolean?
  x : any
Returns #t if x represents a MySQL database connection, #f otherwise.

(current-connection)  (or/c connection? #f)
(current-connection connection)  void?
  connection : (or/c connection? #f)
A parameter that determines the default database connection to use when one is not explicitly provided to the procedures that communicate with the database server.

(connect host    
  [#:schema schema    
  #:use-ssl? use-ssl?    
  #:set-current? set-current?])  connection?
  host : string?
  port : exact-nonnegative-integer?
  user : string?
  password : string?
  schema : (or/c string? #f) = #f
  use-ssl? : boolean? = #f
  set-current? : boolean? = #t
Connects to a MySQL server instance, using the supplied parameters.

If schema is not supplied, the connection will initially not be assoicated with any schema.

If use-ssl? is #t, the Client Library will attempt to use an SSL-tunelled TCP connection. This depends upon both the MySQL server having SSL support and the client having the proper OpenSSL libraries. If these conditions are not met, the procedure will raise exn:fail.

If set-current? is #t, the connection returned by this procedure will become the new value of the current-connection parameter.

(close-connection! con)  void?
  con : connection?
Closes the provided connection.

(connection-open? con)  boolean?
  con : connection?
Returns #t if con represents a connection that has not been explicitly closed by the close-connection! procedure.