[Koha] [koha] Authorized value for category_types

Hi team, I am trying to create a report that allows me to get circulation statistics based on the category_type from the categories table rather than categorycode. Putting the values in the query e.g. I for organization patrons, A for adults e.t.c. works well. However, I need to be able to select from a list. I do not know the authorized value for that hence seek your help. I have tried the below filter which says category_type is not an authorized value. WHERE categories.category_type= <<CATEGORY|category_type>> If anyone can help me on the above issue and/or help me know how/where to find such authorized values, I'd be so grateful. Warm Regards James.