class SQLite3::Database

#rollback.
transaction explicitly, either by calling #commit, or by calling
If a block is not given, it is the caller's responsibility to end the

explicitly or you'll get an error when the block terminates.
a block is given, #commit and #rollback should never be called
raises an exception, a rollback will be performed instead. Note that if
transaction is committed when the block terminates. If the block
If a block is given, the database instance is yielded to it, and the

:immediate, or :exclusive.
The +mode+ parameter may be either :deferred (the default),

exception.
by SQLite, so attempting to nest a transaction will result in a runtime
Begins a new transaction. Note that nested transactions are not allowed

def transaction( mode = :deferred )
  execute "begin #{mode.to_s} transaction"
  if block_given?
    abort = false
    begin
      yield self
    rescue
      abort = true
      raise
    ensure
      abort and rollback or commit
    end
  end
  true
end