Currently, it's possible to bulk change the meaning of many columns using the prepare recipe's column view. However, it's not possible to change the types the same way from this interface. While the schema can be changed from the downstream dataset, there's no way to change the target schema of the recipe without manually changing every column's data type. It would save a lot of time in dataset preparation (especially on very wide datasets) if column types could be changed from the column view of the prepare recipe.
