queue.add(function (next) {
						return Dialect.addCollectionColumn(driver, collection.name, col.value, last_k, next);
					});
						col.before(driver, function (err) {
							if (err) {
								return next(err);
							}
							return Dialect.addCollectionColumn(driver, collection.name, col.value, last_k, next);
						});