struct ovsdb_error *ovsdb_column_set_from_json(const struct json *,
const struct ovsdb_table *,
struct ovsdb_column_set *);
+struct json *ovsdb_column_set_to_json(const struct ovsdb_column_set *);
void ovsdb_column_set_add(struct ovsdb_column_set *,
const struct ovsdb_column *);