;;; Per zbigniew's comments on IRC, I have now wrapped the transaction in 
;;; call-with-database, removing the calls to open-database and close-database, 
;;; as well as the unnecessary call to database-closed? The procedure now also 
;;; only makes a single call to sql to prepare the sql statement, which should 
;;; improve performance. Comments welcome. 

;;; Insert a list of records into an SQLite3 database.
;;;   db-file: string, filename of database
;;;   sql-str: string, sql-query string
;;;   records: list, where each element is a list containing record values 
(define (bulk-insert db-file sql-str records)
  (call-with-database db-file
                      (lambda (db)
                        (let* ((stmt (sql db sql-str))
                               (insert (lambda ()
                                         (for-each
                                          (lambda (rec)
                                            (apply exec stmt rec)) records))))
                          (with-transaction db insert)))))